7.1: Energy provides the ability to do work and can exist in many forms.

7.1.a: Work is the process of making objects move through the application of force.

7.1.a.2: Work is a scientific concept that expresses the mathematical relationship between the amount of force needed to move an object and how far it moves. For work to be done, a force must be applied for a distance in the same direction as the motion. An object that does not move has no work done on it, even if forces are being applied.

Ants on a Slant (Inclined Plane)

7.1.a.4: Simple machines can be used to do work. People do “input” work on a simple machine which, in turn, does “output” work in moving an object. Simple machines are not used to change the amount of work to move or lift an object; rather, simple machines change the amount of effort force and distance for the simple machine to move the object.

Ants on a Slant (Inclined Plane)

7.1.a.5: Simple machines work on the principle that a small force applied over a long distance is equivalent work to a large force applied over a short distance.

Ants on a Slant (Inclined Plane)

7.1.a.6: Some simple machines are used to move or lift an object over a greater output distance (snow shovel), or change direction of an object’s motion, but most are used to reduce the amount of effort (input force) required to lift or move an object (output force).

Ants on a Slant (Inclined Plane)

7.1.a.7: An inclined plane is a simple machine that reduces the effort force needed to raise an object to a given height. The effort force and distance and output force and distance depend on the length and height (steepness) of the inclined plane.

Ants on a Slant (Inclined Plane)

7.1.a.9: A lever is a simple machine that reduces the effort force needed to lift a heavy object by applying the force at a greater distance from the fulcrum of the lever. The effort force and distance, output force and distance, and direction of motion all depend on the position of the fulcrum in relationship to the input and output forces.

Levers

7.1.a.10: The mechanical advantage of a simple machine indicates how useful the machine is for performing a given task by comparing the output force to the input force. The mechanical advantage is the number of times a machine multiplies the effort force. The longer the distance over which the effort force is applied, the greater the mechanical advantage of the machine.

Levers
Pulleys
Wheel and Axle

7.1.a.11: The mechanical advantage of a machine can be calculated by dividing the resistance force by the effort force. Usually, the resistance force is the weight of the object in newtons.

Levers
Pulleys
Wheel and Axle

7.1.b: Energy can be stored in many forms and can be transformed into the energy of motion.

7.1.b.2: Potential energy is the capacity for doing work that a body possesses because of its position or condition. It is evident as gravitational potential energy (an object about to roll down a hill), elastic potential energy (a stretched rubber band) or chemical potential energy (carbohydrates in foods).

Energy of a Pendulum
Inclined Plane - Sliding Objects
Potential Energy on Shelves
Roller Coaster Physics

7.1.b.3: Kinetic energy is energy a body possesses because it is in motion.

Air Track
Energy of a Pendulum
Inclined Plane - Sliding Objects
Roller Coaster Physics
Sled Wars

7.1.b.5: When energy is transformed, the total amount of energy stays constant (is conserved).

Air Track
Energy Conversion in a System
Energy of a Pendulum
Inclined Plane - Sliding Objects
Roller Coaster Physics

7.1.b.6: Work is done to lift an object, giving it gravitational potential energy (weight x height). The gravitational potential energy of an object moving down a hill is transformed into kinetic energy as it moves, reaching maximum kinetic energy at the bottom of the hill.

Energy of a Pendulum
Inclined Plane - Sliding Objects
Roller Coaster Physics
Sled Wars

7.1.b.7: Some kinetic energy is always transformed into heat by friction; therefore, the object will never reach the same height it started from again without added energy.

Energy Conversion in a System

7.2: Many organisms, including humans, have specialized organ systems that interact with each other to maintain dynamic internal balance.

7.2.a: All organisms are composed of one or more cells; each cell carries on life-sustaining functions.

7.2.a.2: Organisms are made of tiny cells that perform the basic life functions and keep the organism alive. Many organisms (for example yeast, algae) are single-celled, and many organisms (for example plants, fungi and animals) are made of millions of cells that work in coordination.

Cell Structure
Paramecium Homeostasis

7.2.a.4: The cell is filled with a fluid called cytoplasm; cells contain discrete membrane-enclosed structures called organelles that perform specific functions that support the life of the organism. The structure of the organelle is related to its function.

7.2.a.4.a: The nucleus contains the genetic materials (chromosomes), and it directs the cell activities, growth and division.

Cell Division
Human Karyotyping

7.2.b: Multicellular organisms need specialized structures and systems to perform basic life functions.

7.2.b.4: Different tissues work together to form an organ, and organs work together as organ systems to perform essential life functions.

Digestive System

7.2.b.13: The major parts of the human digestive system are the mouth, esophagus, stomach, small intestine and large intestine. This system is responsible for breaking down food, absorbing nutrients and water, and eliminating waste. The liver and pancreas support the functions of the major digestive organs by producing and releasing digestive liquids into the digestive tract.

Digestive System

7.2.b.14: The nervous, immune and excretory systems interact with the digestive, respiratory and circulatory systems to maintain the body’s dynamic internal balance (homeostasis).

Circulatory System
Human Homeostasis

7.3: Landforms are the result of the interaction of constructive and destructive forces over time.

7.3.a: Volcanic activity and the folding and faulting of rock layers during the shifting of the earth’s crust affect the formation of mountains, ridges and valleys.

7.3.a.1: Earth’s surface features, such as mountains, volcanoes and continents, are the constantly changing result of dynamic processes and forces at work inside the earth.

Plate Tectonics

7.3.a.5: Tectonic plates meet and interact at divergent, convergent or transform boundaries. The way in which the plates interact at a boundary affects outcomes such as folding, faulting, uplift or earthquakes.

Plate Tectonics

7.3.a.6: The folding and faulting of rock layers during the shifting of the earth’s crust causes the constructive formation of mountains, ridges and valleys.

Plate Tectonics

7.3.a.7: Mountain formation can be the result of convergent tectonic plates colliding, such as the Appalachians and the Himalayas; mountains may also be formed as a result of divergent tectonic plates moving apart and causing rifting as in East Africa or Connecticut.

Plate Tectonics

7.3.a.8: Most volcanoes and earthquakes are located at tectonic plate boundaries where plates come together or move apart from each other. A geographic plot of the location of volcanoes and the centers of earthquakes allows us to locate tectonic plate boundaries.

Plate Tectonics

7.3.a.9: The geological makeup of Connecticut shows evidence of various earth processes, such as continental collisions, rifting, and folding that have shaped its structure

Plate Tectonics

7.3.b: Glaciation, weathering and erosion change the earth’s surface by moving earth materials from place to place.

7.3.b.1: Earth’s surface is constantly being shaped and reshaped by natural processes. Some of these processes, like earthquakes and volcanic eruptions, produce dramatic and rapid change. Others, like weathering and erosion, usually work less conspicuously over longer periods of time.

Rock Cycle