Question

calculate the initial gravitational potential energy Ug in units of Joules
calculate the final kinetic energy at the bottom of ramp K in units of Joules
how does Ug compare to K: same, or Ug greater, or K?
Based on conservation of energy, Ug should equal K, right? Explain why or why not from data and your calculations.

data:

Length of ramp track: 102 cm
mass of cart: 254.4 g
Height of ramp at top relative to table top: 34 cm
Height of ramp at bottom relative to table top: 6 cm
Average time for cart to go from top to bottom: 0.75

Answer 1

The P.E. at the top relative to bottom is = 0.85 - 0.15 =.70 J

We can see that the P.E. at the top is greater than the K.E. at the bottom of the ramp. But the energy is always conserved, so there must be some energy loss while coming from top to bottom. This is possible if ramp is not smooth and there is energy loss due to friction.