Work and Kinetic Energy Lab, investigating the relationship between the work done on a cart and the change in the kinetic energy of the cart. We used a cart, track, 3- 20 g masses, and a photogate.

Basically we place started with the 20 g mass attached to the end of a string. We moved the cart to the end of the track so the 20 g mass was hanging at 80 cm above the floor. We then measured distance from the bottom on the 20 g mass to the floor and recorded it below and release the cart. We did this again for each mass. Below is the data recorded.

Mass HeightWork Velocity Total Kinetic Energy

20g 42cm? .507cm/s ?

40g42cm ?.691 cm/s?

60g42cm ? .876 cm/s?

Can you help me understand how to calculate the work done by the falling mass? W=mgh The car and the picket fence used had a total mass of 500g.

1)Calculate the work done by the falling mass in the table above.

2)Calculate kinetic energy of cart and the falling mass. *The car and the picket fence used had a total mass of 500g.

3) Finally when comparing the work done by the falling mass to the total change in kinetic energy for the cart and the falling mass, why might there be a difference?