Standards for Teaching and Learning
ES.2.2: Describe various instrumentation used to study deep space and the solar system (e.g., telescopes which record in various parts of the electromagnetic spectrum, including visible, infrared, and radio, refracting telescope, reflecting telescope, spectrophotometer.)
ES.2.6: Analyze the life histories of stars and different types of stars found on the Hertzsprung-Russell diagram, including the three outcomes of stellar evolution based on mass (black hole, neutron star, white dwarf).
ES.3.1: Describe the location of the solar system in an outer edge of the disc-shaped Milky Way galaxy, which spans 100,000 light years.
ES.3.2: Compare and contrast the differences in size, temperature, and age between our sun and other stars.
ES.3.4: Observe and describe the characteristics and motions of the various kinds of objects in our solar system, including planets, satellites, comets, and asteroids, and the influence of gravity and inertia on these motions.
ES.3.5: Explain how Kepler's laws predict the orbits of the planets.
ES.4.2: Investigate and describe the composition of the Earth's atmosphere as it has evolved over geologic time (outgassing, origin of atmospheric oxygen, variations in carbon dioxide concentration).
ES.4.4: Explain the effects on climate of latitude, elevation, and topography, as well as proximity to large bodies of water and cold or warm ocean currents.
ES.4.5: Explain the possible mechanisms and effects of atmospheric changes brought on by things such as acid rain, smoke, volcanic dust, greenhouse gases, and ozone depletion.
ES.4.8: Explain special properties of water (e.g., high specific and latent heats) and the influence of large bodies of water and the water cycle on heat transport and therefore weather and climate.
ES.4.9: Describe the development and dynamics of climatic changes over time corresponding to changes in the Earth's geography (continental drift), orbital parameters (the Milankovitch cycles), and atmospheric composition.
ES.4.11: Explain that the oceans store carbon dioxide mostly as dissolved HCO3 and CaCO3 as precipitate or biogenic carbonate deposits.
ES.4.13: Use computer models to predict the effects of increasing greenhouse gases on climate for the planet as a whole and for specific regions.
ES.5.1: Explain how water flows into and through a watershed (e.g. properly use terms precipitation, aquifers, wells, porosity, permeability, water table, capillary water, and run off).
ES.5.2: Describe the processes of the hydrologic cycle, including evaporation, condensation, precipitation, surface runoff and groundwater percolation, infiltration, and transpiration.
ES.5.3: Identify and explain the mechanisms that cause and modify the production of tides, such as the gravitational attraction of the moon, the sun, and coastal topography.
ES.6.1: Differentiate among the processes of weathering, erosion, transportation of materials, deposition, and soil formation.
ES.6.2: Illustrate the various processes and rock types that are involved in the rock cycle, and describe how the total amount of material stays the same throughout formation, weathering, sedimentation, and reformation.
ES.6.4: Recognize and explain geologic evidence - including fossils and radioactive dating - which indicates the age of the Earth.
ES.7.2: Analyze the evidence that supports the hypothesis of movement of the plates (from paleomagnetism, paleontology, paleoclimate, and the continuity of geological structure and stratigraphy across ocean basins).
ES.7.3: Trace the development of a lithospheric plate from its growing margin at a divergent boundary (mid-ocean ridge) to its destructive margin at a convergent boundary (subduction zone).
ES.7.4: Explain the relationship between convection currents and the motion of the lithospheric plates.
ES.7.5: Explain why, how, and where earthquakes occur, how they are located and measured, and the ways that they can cause damage (directly by shaking and secondarily by fire, tsunami, landsliding, or liquefaction).
B.2.1: Using simplified Bohr diagrams, describe basic atomic structure in order to understand the basis of chemical bonding in covalent and ionic bonds.
B.2.2: Describe the structure and unique properties of water and its importance to living things.
B.2.3: Describe the central role of carbon in the chemistry of living things because of its ability to combine in many ways with itself and other elements.
B.2.4: Know that living things are made of molecules largely consisting of carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur.
B.2.6: Observe and explain the role of enzymatic catalysis in biochemical processes.
B.2.7: Explain the hierarchical organization of living things from least complex to most complex (subatomic, atomic, molecular, cellular, tissue, organs, organ system, organism, population, community, ecosystem, biosphere).
B.3.1: Compare and contrast the general anatomy and constituents of prokaryotic and eukaryotic cells and their distinguishing features: Prokaryotic cells do not have a nucleus and eukaryotic cells do. Know prokaryotic organisms are classified in the Monera Kingdom and that organisms in the other four kingdoms have eukaryotic cells.
B.3.2: Understand the function of cellular organelles and how the organelles work together in cellular activities (e.g., enzyme secretion from the pancreas).
B.3.3: Observe and describe that within the cell are specialized parts for the transport of materials, energy capture and release, waste disposal, and motion of the whole cell or of its parts.
B.3.4: Describe the organelles that plant and animal cells have in common (e.g., ribosomes, golgi bodies, endoplasmic reticulum) and some that differ (e.g., only plant cells have chloroplasts and cell walls).
B.3.5: Demonstrate and explain that cell membranes act as highly selective permeable barriers to penetration of substances by diffusion or active transport.
B.3.6: Explain that some structures in the eukaryotic cell, such as mitochondria, and in plants, chloroplasts, have apparently evolved by endosymbiosis (one organism living inside another, to the advantage of both) with early prokaryotes.
B.3.7: Describe that the work of the cell is carried out by structures made up of many different types of large (macro) molecules that it assembles, such as proteins, carbohydrates, lipids, and nucleic acids.
B.3.8: Demonstrate that most cells function best within a narrow range of temperature and pH; extreme changes usually harm cells, by modifying the structure of their macromolecules and, therefore, some of their functions.
B.3.9: Explain that a complex network of proteins provides organization and shape to cells.
B.3.10: Explain that complex interactions among the different kinds of molecules in the cell cause distinct cycles of activities, such as growth and division.
B.3.11: Describe that all growth and development of organisms is a consequence of an increase in cell number, size, and/or products.
B.3.12: Explain how cell activity in a multicellular plant or animal can be affected by molecules from other parts of the organism.
B.3.13: Explain why communication and/or interaction are required between cells to coordinate their diverse activities.
B.3.14: Recognize and describe that cellular respiration is important for the production of ATP, which is the basic energy source for cell metabolism.
B.3.15: Differentiate between the functions of mitosis and meiosis: Mitosis is a process by which a cell divides into each of two daughter cells, each of which has the same number of chromosomes as the original cell. Meiosis is a process of cell division in organisms that reproduce sexually, during which the nucleus divides eventually into four nuclei, each of which contains half the usual number of chromosomes.
B.3.17: Describe that all organisms begin their life cycles as a single cell, and in multicellular organisms the products of mitosis of the original zygote form the embryonic body.
B.4.1: Research and explain the genetic basis for Gregor Mendel's laws of segregation and independent assortment.
B.4.3: Explain how hereditary information is passed from parents to offspring in the form of "genes" which are long stretches of DNA consisting of sequences of nucleotides. Explain that in eukaryotes, the genes are contained in chromosomes, which are bodies made up of DNA and various proteins.
B.4.5: Explain the flow of information is usually from DNA to RNA, and then to protein.
B.4.7: Understand that and describe how inserting, deleting, or substituting short stretches of DNA alters a gene. Recognize that changes (mutations) in the DNA sequence in or near a specific gene may (or may not) affect the sequence of amino acids in the encoded protein or the expression of the gene.
B.4.8: Explain the mechanisms of genetic mutations and chromosomal recombinations, and when and how they are passed on to offspring.
B.4.9: Understand and explain that specialization of cells is almost always due to different patterns of gene expression rather than differences in the genes themselves.
B.4.10: Explain how the sorting and recombination of genes in sexual reproduction result in a vast variety of potential allele combinations in the offspring of any two parents.
B.4.11: Explain that genetic variation can occur from such processes as crossing over, jumping genes, and deletion and duplication of genes.
B.4.12: Explain how the actions of genes, patterns of inheritance, and the reproduction of cells and organisms account for the continuity of life.
B.4.13: Investigate and describe how a biological classification system that implies degrees of kinship between organisms or species can be deduced from the similarity of their nucleotide (DNA) or amino acids (protein) sequences. Know that such systems often match the completely independent classification systems based on anatomical similarities.
B.5.1: Investigate and explain how molecular evidence reinforces and confirms the fossil, anatomical, and other evidence for evolution and provides additional detail about the sequence in which various lines of descent branched off from one another.
B.5.2: Explain how a large diversity of species increases the chance that at least some living things will survive in the face of large or even catastrophic changes in the environment.
B.5.3: Research and explain how natural selection provides a mechanism for evolution and leads to organisms that are optimally suited for survival in particular environments.
B.5.4: Explain that biological diversity, episodic speciation, and mass extinction are depicted in the fossil record, comparative anatomy, and other evidence.
B.5.5: Describe how life on Earth is thought to have begun as one or a few simple one-celled organisms about 3.5 billion years ago, and that during the first 2 billion years, only single-cell microorganisms existed. Know that, once cells with nuclei developed about a billion years ago, increasingly complex multicellular organisms could evolve.
B.5.6: Explain that prior to the theory first offered by Charles Darwin and Alfred Wallace, the universal belief was that all known species had been created de novo at about the same time and had remained unchanged.
B.5.7: Research and explain that Darwin argued that only biologically inherited characteristics could be passed on to offspring, some of these characteristics would be different from the average and advantageous in surviving and reproducing, and over generations, accumulation of these inherited advantages would lead to a new species.
B.5.8: Explain Gregor Mendel's identification of what we now call "genes" and how they are sorted in reproduction led to an understanding of the mechanism of heredity. Understand how the integration of his concept of heredity and the concept of natural selection has led to the modern model of speciation and evolution.
B.5.10: Explain that evolution builds on what already exists, so the more variety there is, the more there can be in the future.
B.6.4: Explain the photosynthesis process: Plants make food in their leaves and chlorophyll found in the leaves can make food the plant can use from carbon dioxide, water, nutrients, and energy from sunlight.
B.6.5: Explain that during the process of photosynthesis, plants release oxygen into the air.
B.6.6: Describe that plants have broad patterns of behavior that have evolved to ensure reproductive success, including co-evolution with animals that distribute a plant's pollen and seeds.
B.8.2: Describe how factors in an ecosystem, such as the availability of energy, water, oxygen, and minerals and the ability to recycle the residue of dead organic materials, cause fluctuations in population sizes.
B.8.3: Explore and explain how changes in population size have an impact on the ecological balance of a community and how to analyze the effects.
B.8.6: Explain that ecosystems tend to have cyclic fluctuations around a state of rough equilibrium, and change results from shifts in climate, natural causes, human activity, or when a new species or non-native species appears.
B.8.7: Explain how layers of energy-rich organic material, mostly of plant origin, have been gradually turned into great coal beds and oil pools by the pressure of the overlying Earth and its internal heat.
B.8.9: Investigate and describe how point and non-point source pollution can affect the health of a bay's watershed and wetlands.
B.8.10: Assess the method for monitoring and safeguarding water quality, including local waterways such as the Anacostia and Potomac rivers, and know that macro-invertebrates can be early warning signs of decreasing water quality.
C.2.1: Investigate and classify properties of matter, including density, melting point, boiling point, and solubility.
C.2.2: Determine the definitions of and use properties such as mass, volume, temperature, density, melting point, boiling point, conductivity, solubility, and color to differentiate between types of matter.
C.2.3: Know the concept of a mole in terms of number of particles, mass, and the volume of an ideal gas at specified conditions of temperature and pressure.
C.2.4: Distinguish between the three familiar states of matter (solid, liquid, gas) in terms of energy, particle motion, and phase transitions and describe what a plasma is.
C.2.5: Infer and explain that physical properties of substances, such as melting points, boiling points, and solubility are due to the strength of their various types (interatomic, intermolecular, or ionic) of bonds.
C.2.6: Write equations that describe chemical changes and reactions.
C.2.7: Classify substances as metal or non-metal, ionic or molecular, acid or base, and organic or inorganic, using formulas and laboratory investigations.
C.3.3: Illustrate and explain the pH scale to characterize acid and base solutions: Neutral solutions have pH 7, acids are less than 7, and bases are greater than 7.
C.4.1: Detail the development of atomic theory from the ancient Greeks to the present (Democritus, Dalton, Rutherford, Bohr, quantum theory).
C.4.2: Explain Dalton's atomic theory in terms of the laws of conservation of matter, definite composition, and multiple proportions.
C.4.3: Demonstrate and explain how chemical properties depend almost entirely on the configuration of the outer electron shell, which in turn depends on the proton number.
C.4.4: Explain the historical importance of the Bohr model of the atom.
C.4.5: Construct a diagram and describe the number and arrangement of subatomic particles within an atom or ion.
C.4.6: Describe that spectral lines are the result of transitions of electrons between energy levels.
C.4.7: Describe that spectral lines correspond to photons with a frequency related to the energy spacing between levels by using Planck's formula (E = hv) in calculations.
C.5.1: Relate an element's position on the periodic table to its atomic number (number of protons).
C.5.2: Relate the position of an element in the periodic table and its reactivity with other elements to its quantum electron configuration.
C.5.3: Use the periodic table to compare trends in periodic properties, such as ionization energy, electronegativity, electron affinity, and relative size of atoms and ions.
C.5.4: Use an element's location in the periodic table to determine its number of valence electrons, and predict what stable ion or ions an element is likely to form in reacting with other specified elements.
C.6.1: Explain how protons and neutrons in the nucleus are held together by strong nuclear forces that just balance the electromagnetic repulsion between the protons in a stable nucleus.
C.6.3: Know many naturally occurring isotopes of elements are radioactive, as are isotopes formed in nuclear reactions.
C.6.4: Describe the process of radioactive decay as the spontaneous breakdown of certain unstable (radioactive) elements into new elements (radioactive or not) through the spontaneous emission by the nucleus of alpha, or beta particles, or gamma radiation.
C.6.5: Predict and explain that the alpha, beta, and gamma radiation produced in radioactive decay produce different amounts and kinds of damage in matter and have different ranges of penetration.
C.6.6: Explain that the half-life of a radioactive element is the time it takes for the radioactive element to lose one-half its radioactivity and calculate the amount of radioactive substance remaining after an integral number of half-lives have passed.
C.7.1: Explain how Arrhenius' discovery of the nature of ionic solutions contributed to the understanding of a broad class of chemical reactions.
C.7.2: Predict and explain how atoms combine to form molecules by sharing electrons to form covalent or metallic bonds, or by transferring electrons to form ionic bonds.
C.7.3: Recognize names and chemical formulas for simple molecular compounds (such as N2O3), ionic compounds, including those with polyatomic ions, simple organic compounds, and acids, including oxyacids (such as HClO4).
C.7.5: Demonstrate and explain that chemical bonds between identical atoms in molecules such as H2, O2, CH4, NH3, C2H4, N2, H2O, and many large biological molecules tend to be covalent; some of these molecules may have hydrogen bonds between them. In addition, molecules have other forms of intermolecular bonds, such as London dispersion forces and/or dipole bonding.
C.7.6: Explain that in solids, particles can only vibrate around fixed positions, but in liquids, they can slide randomly past one another, and in gases, they are free to move between collisions with one another.
C.7.7: Draw Lewis dot structures for atoms, molecules and polyatomic ions.
C.7.8: Predict the geometry and polarity of simple molecules, and explain how these influence the intermolecular attraction between molecules.
C.7.9: Predict chemical formulas based on the number of valence electrons.
C.8.3: Classify reactions of various types such as single and double replacement, synthesis, decomposition, and acid/base neutralization.
C.8.4: Calculate the masses of reactants and products in a chemical reaction from the mass of one of the reactants or products and the relevant atomic or molecular masses).
C.8.6: Determine molar mass of a molecule given its chemical formula and a table of atomic masses.
C.8.7: Convert the mass of a molecular substance to moles, number of particles, or volume of gas at standard temperature and pressure.
C.8.10: Use changes in oxidation states to recognize electron transfer reactions, and identify the substance(s) losing and gaining electrons in an electron transfer reaction.
C.8.11: Describe the effect of changes in reactant concentration, changes in temperature, the surface area of solids, and the presence of catalysts on reaction rates.[
C.9.1: Explain the kinetic molecular theory and use it to explain changes in gas volumes, pressure, and temperature.
C.9.2: Apply the relationship between pressure and volume at constant temperature (Boyle's law, pV = constant at constant temperature and number of moles), and between volume and temperature (Charles' law or Gay-Lussac's law, V/T = constant at constant pressure and number of moles) and the relationship between pressure and temperature that follows from them.
C.9.3: Solve problems using the Ideal Gas law, pV = nRT, and the combined gas law, p1V1/T1= p2V2/T2.
C.9.5: Apply Graham's Law of Diffusion.
C.10.1: Explain how equilibrium is established when forward and reverse reaction rates are equal.
C.10.2: Describe the factors that affect the rate of a chemical reaction (temperature, concentration) and the factors that can cause a shift in equilibrium (concentration, pressure, volume, temperature).
C.10.3: Explain why rates of reaction are dependent on the frequency of collision, energy of collisions, and orientation of colliding molecules.
C.10.4: Observe and describe the role of activation energy and catalysts in a chemical reaction.
C.10.6: Write the equilibrium expression for a given reaction and calculate the equilibrium constant for the reaction from given concentration data.
C.11.2: Predict and describe how the temperature, concentration, pressure and surface area of solids affect the dissolving process.
C.11.3: Explain that, for a closed system at constant temperature and pressure, a solid in contact with its saturated solution may reach dynamic equilibrium in that the rate of solid dissolving equals the rate of solid precipitating.
C.11.4: Calculate the concentration units of solutions such as molarity, percent by mass or volume, parts per million (ppm), or parts per billion (ppb).
C.11.6: Calculate the theoretical freezing-point depression and boiling-point elevation of an ideal solution as a function of solute concentration.
C.12.1: Describe the concepts of temperature and heat flow in terms of the motion and energy of molecules (or atoms).
C.12.3: Explain how energy is released when a material condenses or freezes and is absorbed when a material evaporates or melts.
C.12.4: Solve problems involving heat flow and temperature changes, using given values of specific heat and latent heat of phase change.
C.13.1: Explain how the bonding characteristics of carbon lead to a large variety of structures ranging from simple hydrocarbons to complex polymers and biological molecules.
C.13.4: Convert between chemical formulas, structural formulas, and names of simple common organic compounds (hydrocarbons, proteins, fats, carbohydrates).
P.2.1: Explain Newton's first law: When the net force on an object is zero, no acceleration occurs, and thus a moving object continues to move at a constant speed in the same direction, or, if at rest, it remains at rest.
P.2.2: Explain that only when a net force is applied to an object will its motion change; that is, it will accelerate according to Newton's second law, F = ma.
P.2.3: Predict and explain how when one object exerts a force on a second object, the second object always exerts a force of equal magnitude but of opposite direction and force back on the first: F1 on 2 = -F2 on 1. (Newton's third law).
P.2.4: Explain that Newton's laws of motion are not universally applicable, but they provide very good approximations unless an object is moving close to the speed of light or is small enough that quantum effects are important.
P.2.5: Explain that every object in the universe exerts an attractive force on every other object. Know the magnitude of the force is proportional to the product of the masses of the two objects and inversely proportional to the distance between them: F = G m1m2/r².
P.2.6: Investigate and explain how the Newtonian model - the three laws of motion plus the law of gravitation - makes it possible to account for such diverse phenomena as tides, the orbits of the planets and moons, the motion of falling objects, and Earth's equatorial bulge.
P.2.7: Explain how a force acting on an object perpendicular to the direction of its motion causes it to change direction but not speed.
P.2.8: Demonstrate that a motion at constant speed in a circle requires a force that is always directed toward the center of the circle.
P.2.9: Solve kinematics problems involving constant speed and average speed.
P.2.10: Apply the law F = ma to solve one-dimensional motion problems involving constant forces (Newton's second law).
P.2.11: Use and mathematically manipulate appropriate scalar and vector quantities (F, v, a, delta r, m, g) to solve kinematics and dynamics problems in one and two dimensions.
P.2.12: Solve problems in circular motion, using the formula for centripetal acceleration in the following form: a = v²/r.
P.2.13: Create and interpret graphs of speed versus time and the position and speed of an object undergoing constant acceleration.
P.3.1: Recognize that when a net force, F, acts through a distance delta x on an object of mass m, which is initially at rest, work W = F delta x, is done on the object; the object acquires a velocity, v, and a kinetic energy, K = ½ mv² = W = F delta x.
P.3.2: Describe how an unbalanced force, F, acting on an object over time, delta t, results in a change, delta p = F delta t, in the object's momentum.
P.3.3: Describe how kinetic energy can be transformed into potential energy and vice versa (e.g., a bouncing ball).
P.3.4: Explain that momentum is a separately conserved quantity that is defined in one dimension as p = mv. Know the momentum of a system can be changed only by application of an external impulse, J = F delta t. Know the total momentum of a closed system cannot change, regardless of the interchange of momentum within it.
P.3.6: Identify the joule (J) as the SI unit for work and energy); the unit for power is the watt (W); and the unit for impulse and momentum is the kg·m/s.
P.3.7: Describe the conditions under which each conservation law applies.
P.3.8: Calculate kinetic energy using the formula K = ½mv²
P.3.9: Calculate changes in gravitational potential energy, U, due to elevation changes, delta h, near the Earth using the relation delta U = mg delta h.
P.3.10: Solve problems involving conservation of energy in simple systems such as that of falling objects.
P.3.11: Apply the law of conservation of mechanical energy to simple systems.
P.3.12: 1Calculate the momentum of an object as the product p = mv.
P.3.13: Solve problems involving perfectly inelastic collisions in one dimension using the principle of conservation of momentum.
P.3.14: Calculate the changes in motion of two bodies in one-dimensional elastic collisions in which both energy and momentum are conserved.
P.4.1: Explain that the buoyant force on an object in a fluid is an upward force equal to the weight of the fluid it has displaced.
P.4.3: Identify that the pressure in an incompressible fluid (e.g., water) is a function of density, ρ; depth, y; and gravitational acceleration, g.
P.4.4: Solve problems involving floating and sinking bodies using Archimedes' principle.
P.4.5: Understand Bernoulli's principle, p + ½ ρv² = constant is a consequence of conservation of mechanical energy applied to a moving, incompressible fluid, and apply it accurately.
P.4.6: Solve problems involving a confined, isothermal gas using Boyle's law.
P.5.1: Recognize that heat flow and work are two forms of energy transfer between a system and its surroundings.
P.5.2: Describe and measure the change, delta U, in the internal energy of a system is equal to the sum of the heat flow, Q, into the system and the work, W, done on the system: delta U = Q + W (first law of thermodynamics).
P.5.3: Describe and measure the work, W, done by a heat engine is the difference between the heat flow, Qin, into the engine at high temperature and the heat flow, Qout, out at a lower temperature: W = Qin - Qout.
P.5.4: Explain that thermal energy (commonly called heat) consists of random motion and the vibrations and rotations of atoms, molecules, or ions.
P.5.5: Describe how in everyday practice, temperature is measured with a thermometer, a device containing a part that has a thermometric parameter (a quantity that changes with temperature).
P.5.6: Investigate and describe how the absolute temperature of an object is proportional to the average kinetic energy of the thermal motion of its microscopic parts.
P.5.7: Recognize that the absolute temperature is measured in kelvins (K); 0 K is the temperature at which the average kinetic energy of the microscopic parts of the system is an irreducible minimum.
P.5.9: Describe that when two objects at different temperatures are in contact, heat energy always flows from the object at a higher temperature to the object at a lower temperature by the process of conduction until the two are at the same (intermediate) temperature.
P.5.10: Explain the process of convection: Because the density of fluids varies with temperature, the warmer parts of a fluid tend to move into and mix with the cooler parts, resulting in a transfer of heat energy from place to place.
P.5.11: Explain that all objects emit electromagnetic radiation at a rate that rises very rapidly with their temperature. As a result, know that a warmer body that is in the line of sight with a cooler one will transfer net energy to it, cooling down while the cooler object warms up.
P.5.12: Demonstrate that in all internal energy transfers, the overall effect is that the energy is spread out uniformly.
P.5.15: Use a p-V diagram to graph simple thermodynamic processes for an ideal gas (for which pV = nRT); for example, an isothermal process is described by a hyperbola, an isobaric process by a horizontal straight line, and an isochoric process by a vertical straight line.
P.5.16: Use the second-law-based Carnot efficiency formula, eta = (Tin - Tout)/Tin , to calculate the maximum possible efficiency for a heat engine.
P.5.17: Given heat input and work output data, calculate the efficiency of a real heat engine or human being (e.g., a well-trained athlete working out for eight hours may consume 7,000 kcal of food (20 MJ) a day and do work at the rate of ¼ HP (187 W) over an eighthour period during that day. What is his thermodynamic efficiency?).
P.6.1: Explain that waves carry energy from one place to another.
P.6.2: Observe and describe that a mechanical wave is a disturbance in a medium. For example, a sound wave in air is a slight variation in the pressure of the air surrounding a vibrating object, such as a bell.
P.6.3: Explain that waves conform to the superposition principle: Any number of waves can pass through the same point at the same time, and the amplitude, A, of the resulting wave at that point at any time is the sum of the amplitudes of the superposed waves. Use the principle of superposition to describe the interference effects arising from propagation of several waves through the same medium.
P.6.4: Demonstrate how standing waves on a stretched string are the result of the superposition of the wave moving away from the source and the wave reflected back from the other end of the string.
P.6.5: Explain that longitudinal waves can propagate in any medium, but transverse waves can propagate only in solids.
P.6.6: Describe that sound in a fluid medium is a longitudinal wave whose speed depends on the properties of the medium in which it propagates.
P.6.7: Differentiate electromagnetic waves from mechanical waves (i.e., Electromagnetic waves are not disturbances in a medium. Rather, such waves are a combination of a varying electric field and a varying magnetic field, each of which, in varying, gives rise to the other. Electromagnetic waves can therefore propagate in empty space.)
P.6.9: Explain how Scottish physicist James Clerk Maxwell used Ampère's law and Faraday's law to predict the existence of electromagnetic waves and predict that light was just such a wave. Know these predictions were confirmed by Heinrich Hertz, whose confirmations thus made possible the fields of radio, television, and many other technologies.
P.6.10: Predict and explain how light travels through a transparent medium at a speed, v, less than c. The index of refraction of the medium is defined to be n = c/v.
P.6.11: Explain that when a light ray passes from air into a transparent substance, such as glass, having index of refraction n, it is refracted through an angle given by Snell's law, n sin theta i = n sin theta r , where theta i is the angle of incidence of the ray and theta r is the angle of refraction.
P.6.12: Describe waves in terms of their fundamental characteristics of speed, v; wavelength, gamma; frequency, f; or period, T, and amplitude, A, and the relationships among them. For example, f gamma = v, f = 1/T. Solve problems involving wavelength, frequency, and wave speed.
P.6.13: Identify transverse and longitudinal waves in mechanical media such as springs, ropes, and the Earth (seismic waves).
P.6.14: Identify the phenomena of interference (beats), diffraction, refraction, the Doppler effect, and polarization, and that these are characteristic wave properties.
P.6.15: Use Snell's law to calculate refraction angles and analyze the properties of simple optical systems.
P.6.16: Identify electromagnetic radiation as a wave phenomenon after observing interference, diffraction, and polarization of such radiation.
P.7.1: Determine how an electric charge, q, exists in two kinds: positive (+) and negative (-). Know that like charges repel each other, and unlike charges attract each other with an electrostatic force whose magnitude is given by Coulomb's law, F = k q1q2/r12² , where k is a constant. Know the unit of electric charge is the coulomb (C).
P.7.6: Give evidence that metals are almost all good electrical conductors, nevertheless they do offer some resistance (friction) to the flow of current. Know that the greater the potential difference between the ends of the conductor, the greater the current; the greater the resistance, the less the current. Know too, that for most metals and many other conductors, the current is determined by Ohm's law, V = IR. A conductor that conforms to this rule is called an ohmic conductor.
P.7.7: Explain that any resistive element in a dc circuit transforms electrical energy into thermal energy at a rate (power) given by Joule's law, P = IV, which in an ohmic element has the special form P = I²R = V²/R.
P.7.8: Recognize that plasmas, the fourth state of matter, contain ions and free electrons in such numbers that they are electrically neutral overall, but the many free charges they contain make them good conductors of electricity. Recognize that the glowing gas in a neon light is plasma.
P.7.17: Predict the current in simple direct current electric circuits constructed from batteries, wires, and resistors.
P.7.18: Solve problems involving Ohm's law in series and parallel circuits.
P.7.20: Explain the operation of electric generators, motors, and transformers in terms of Ampère's law and Faraday's law.
P.8.1: Explain the research of Marie Curie, later in collaboration with her husband, Pierre, spurred the study of radioactivity and led to the realization that one kind of atom may change into another kind, and so atoms must be made up of smaller parts. Rutherford, Geiger, and Marsden found these parts to be small, dense nuclei surrounded by much larger clouds of electrons.
P.8.2: Recognize that the nucleus, although it contains nearly all of the mass of the atom, occupies less of the atom than the proportion of the solar system occupied by the sun.
P.8.3: Explain how the mass of a neutron or a proton is about 2,000 times greater than the mass of an electron.
P.8.4: Describe Niels Bohr's model of the atom, its electron arrangement, and the correlation with the hydrogen spectrum.
P.8.5: Explain Albert Einstein's photoelectric effect.
P.8.6: Describe Louis de Broglie's insight into the wave-particle duality.
P.8.9: Demonstrate how the mass of a stable nucleus is always less than the sum of the masses of the protons and neutrons comprising it. Know this is especially true of the elements in the region of the periodic table around iron (26 protons, 30 neutrons) and generally less so of elements with greater or lesser atomic numbers than this.
P.8.10: Explain that if lighter atoms are fused to form atoms closer to iron, or heavier atoms are split to form atoms closer to iron, there is a mass loss. Explain that according to the principle of conservation of mass-energy, this mass loss must be accompanied by a release of energy according to Einstein's mass-energy equation. Know too, because c² is such a large number (is approx. equal to 9 x 10 to the 20th power m²/s²) a small mass loss leads to a large energy release.
E.2.1: Understand and explain that human beings are part of Earth's ecosystems, and that human activities can, deliberately or inadvertently, alter ecosystems.
E.2.4: Recognize and explain that in evolutionary change, the present arises from the materials of the past and in ways that can be explained (e.g., formation of soil from rocks and dead organic matter).
E.3.1: Explain that biodiversity is the sum total of different kinds of organisms in a given ecological community or system, and is affected by alterations of habitats.
E.3.2: Know and describe how ecosystems can be reasonably stable over hundreds or thousands of years.
E.3.3: Understand and describe that if a disaster such as flood or fire occurs, the damaged ecosystem is likely to recover in stages that eventually results in a system similar to the original one.
E.3.4: Understand and explain that ecosystems tend to have cyclic fluctuations around a state of rough equilibrium, and change results from shifts in climate, natural causes, human activity, or when a new species or non-native species appears.
E.3.5: Know that organisms may interact in a competitive or cooperative relationship, such as producer/consumer, predator/prey, parasite/hosts, or as symbionts and explain how these interactions contribute to the stability of an ecosystem.
E.3.6: Recognize and describe the difference between systems in equilibrium and systems in disequilibrium.
E.3.7: Explain how water, carbon, phosphorus and nitrogen cycle between abiotic resources and organic matter in an ecosystem and how oxygen cycles via photosynthesis and respiration. Diagram the cycling of carbon, nitrogen, phosphorus, and water in an ecosystem.
E.3.11: Describe how adaptations in physical structure or behavior may improve an organism's chance for survival and impact an ecosystem.
E.3.12: Describe the concepts of niche and habitat and explain the effects of loss of habitat on a species' survivability.
E.4.1: Explain the concept of carrying capacity.
E.4.2: Demonstrate how resources, such as food supply, the availability of water, and shelter, influence populations.
E.4.4: Describe the effect of overpopulation (i.e., resource depletion and potential elimination of species), the role of predators in maintaining ecosystem stability, and methods of population management.
E.6.1: Compare and contrast the processes of the hydrologic cycle, including evaporation, condensation, precipitation, surface runoff and groundwater percolation, infiltration, and transpiration.
E.6.2: Describe the physical characteristics of wetlands and watersheds and explain how water flows into and through a watershed (e.g., precipitation, aquifers, wells, porosity, permeability, water table, capillary water, and run off).
E.6.4: Examine the dynamics of diverse ecosystems in watersheds and wetlands. Identify various organisms found in Potomac River wetlands and watersheds.
E.6.6: Investigate and describe how point and non-point source pollution can affect the health of a bay's watershed and wetlands.
E.6.7: Collect, record and interpret data from physical, chemical and biological sources to evaluate the health of the Chesapeake Bay watershed and wetlands and describe how the Bay supports a wide variety of plant and animal life that interact with other living and non-living things.
E.7.1: Explain that energy cannot be created or destroyed; however, in many processes energy is transformed into the microscopic form called heat energy, that is, the energy of the disordered motion of atoms.
E.7.2: Explain the meaning of radiation, convection, and conduction (three mechanisms by which heat is transferred to, through, and out of the Earth's system).
E.7.3: Understand and describe how layers of energy-rich organic material have been gradually turned into great coal beds and oil pools by the pressure of the overlying earth. Recognize that by burning these fossil fuels, people are passing stored energy back into the environment as heat and releasing large amounts of carbon dioxide.
E.7.4: Describe how energy derived from the sun is used by green plants to produce chemical energy in the form of sugars (photosynthesis), and this energy is transferred along a food chain from producers (plants) to consumers to decomposers.
E.7.5: Illustrate the flow of energy through various trophic levels of food chains and food webs within an ecosystem. Describe how each link in a food web stores some energy in newly made structures and how much of the energy is dissipated into the environment as heat. Understand that a continual input of energy from sunlight is needed to keep the process going.
E.8.1: Differentiate between natural pollution and pollution caused by humans and give examples of each.
E.8.2: Describe sources of air and water pollution and explain how air and water quality impact wildlife, vegetation, and human health.
E.8.5: Compare and contrast the beneficial and harmful effects of an environmental stressor, such as herbicides and pesticides, on plants and animals. Give examples of secondary effects on other environmental components such as humans, water quality and wildlife.
E.8.7: Recognize and describe important legislation enacted to protect environmental quality, such as the Clean Air Act and the Clean Water Act.
Correlation last revised: 12/2/2009