posted by Anonymous .
The electric motor of a model train accelerates the train from rest to 0.780 m/s in 33.0 ms. The total mass of the train is 510 g. Find the average power delivered to the train during its acceleration.
a = (Vf - Vo) / t,
a = (0.78 - 0) / 0.033s = 23.64m/s^2.
Fn = ma = 0.51 * 23.64 = 12.06N. = Net
W = F*d / t = 12.06 * 0.01287 / 0.033 =
Correction: Po = F*d/t = 4.7Watts.
where did you get the value .01287 for d when calculating for work in the last step of the problem