### Energy and Work (MBL) Pre-lab Assignment

Your name: _____________________

Please print this page, fill it in, and show it to your TF at the start of your lab session.

Part of this experiment involves rolling a cart down an incline, and keeping track of all the different kinds of energy. The simulation below shows a similar experiment, except that in the simulation there is a spring at the bottom of the incline.

Three curves, showing the various kinds on energy, are shown in the graph below the simulation. Identify each. The graphs are plotted versus position, not time. x = 0 is at the top of the ramp.

The red curve is the: | gravitational potential energy | spring potential energy | kinetic energy |

The blue curve is the: | gravitational potential energy | spring potential energy | kinetic energy |

The green curve is the: | gravitational potential energy | spring potential energy | kinetic energy |

Assume there is no friction acting. If you added the three curves, what would you get?

a horizontal line | a line that decreases as the object travels down the slope | a line that increases as the object travels down the slope |

If friction was acting on the cart, what would you get if you added the three curves?

a horizontal line | a line that decreases as the object travels down the slope | a line that increases as the object travels down the slope |

The second simulation shows a similar situation as above, except that the spring has been removed. In this simulation the energy graphs are plotted as a function of time.

What shape is the potential energy vs. time graph? Explain why it has this shape.

What shape is the kinetic energy vs. time graph? Explain why it has this shape.