### Energy, matter, and their interaction

• #### Boyle's Law and Charles' Law

Investigate the properties of an ideal gas by performing experiments in which the temperature is held constant (Boyle's Law), and others in which the pressure remains fixed (Charles' Law). The pressure is controlled through the placement of masses on the lid of the container, and temperature is controlled with an adjustable heat source.

• #### Energy Conversion in a System

A falling cylinder is attached to a rotating propeller that stirs and heats the water in a beaker. The mass and height of the cylinder, as well as the quantity and initial temperature of water can be adjusted. The temperature of the water is measured as energy is converted from one form to another.

• #### Energy of a Pendulum

Perform experiments with a pendulum to gain an understanding of energy conservation in simple harmonic motion. The mass, length, and gravitational acceleration of the pendulum can be adjusted, as well as the initial angle. The potential energy, kinetic energy, and total energy of the oscillating pendulum can be displayed on a table, bar chart or graph.

• #### Half-life

Investigate the decay of a radioactive substance. The half-life and the number of radioactive atoms can be adjusted, and theoretical or random decay can be observed. Data can be interpreted visually using a dynamic graph, a bar chart, and a table. Determine the half-lives of two sample isotopes as well as samples with randomly generated half-lives.

• #### Heat Transfer by Conduction

An insulated beaker of hot water is connected to a beaker of cold water with a conducting bar, and over time the temperatures of the beakers equalize as heat is transferred through the bar. Four materials (aluminum, copper, steel, and glass) are available for the bar.

• #### Inclined Plane - Rolling Objects

Observe and compare objects of different shapes as they roll or slide down an inclined plane. Compare the percentages of translational and rotational kinetic energy for each object, and see how this affects how quickly each object moves. The slope of each ramp can be adjusted, and a variety of materials can be used for the objects and ramps.

• #### Inclined Plane - Simple Machine

Investigate how an inclined plane redirects and reduces the force pulling a brick downward, with or without friction. A toy car can apply a variable upward force on the brick, and the mechanical advantage and efficiency of the plane can be determined. A graph of force versus distance illustrates the concept of work.

• #### Inclined Plane - Sliding Objects

Investigate the energy and motion of a block sliding down an inclined plane, with or without friction. The ramp angle can be varied and a variety of materials for the block and ramp can be used. Potential and kinetic energy are reported as the block slides down the ramp. Two experiments can be run simultaneously to compare results as factors are varied.

• #### Phase Changes

Explore the relationship between molecular motion, temperature, and phase changes. Compare the molecular structure of solids, liquids, and gases. Graph temperature changes as ice is melted and water is boiled. Find the effect of altitude on phase changes. The starting temperature, ice volume, altitude, and rate of heating or cooling can be adjusted.

• #### Potential Energy on Shelves

Compare the potential energy of several objects when you place them on shelves of different heights. Learn that two objects at different heights can have the same potential energy, while two objects at the same height can have different potential energies.

• #### Pulley Lab

Use a pulley system to lift a heavy weight to a certain height. Measure the force required to lift the weight using up to three fixed and three movable pulleys. The weight to be lifted and the efficiency of the pulley system can be adjusted, and the height of the weight and the total input distance are reported.

• #### Roller Coaster Physics

Adjust the hills on a toy-car roller coaster and watch what happens as the car careens toward an egg (that can be broken) at the end of the track. The heights of three hills can be manipulated, along with the mass of the car and the friction of the track. A graph of various variables of motion can be viewed as the car travels, including potential, kinetic, and total energies, and the x- and y- components of position, velocity, and acceleration.

• #### Sled Wars

Explore acceleration, speed, momentum, and energy by sending a sled down a hill into a group of snowmen. The starting height and mass of the sled can be changed, as well as the number of snowmen. In the Two sleds scenario, observe collisions between sleds of different masses and starting heights.

• #### Temperature and Particle Motion

Observe the movement of particles of an ideal gas at a variety of temperatures. A histogram showing the Maxwell-Boltzmann velocity distribution is shown, and the most probable velocity, mean velocity, and root mean square velocity can be calculated. Molecules of different gases can be compared.

• #### Trebuchet

Design your own trebuchet to fling a projectile at a castle wall. All of the dimensions of the trebuchet can be adjusted, as well as the masses of the counterweight and payload. Select a target on the Launch tab, or just see how far your projectile will go.

• #### Waves

Observe and measure transverse, longitudinal, and combined waves on a model of a spring moved by a hand. Adjust the amplitude and frequency of the hand, and the tension and density of the spring. The speed and power of the waves is reported, and the wavelength and amplitude can be measured.