Question

A small object is dropped from the top of a building and falls to the ground. As it falls, accelerating due to gravity, it passes a window. If it has speed v1 at the top of the window, and speed v2 at the bottom of the window, at what point does it have a speed (v1 + v2)/2 ? Neglect the effect of air resistance.

A. It depends on the height of the
window or its distance from the top of the building
B. Above the centre point of the
window
C. Below the centre point of the
window
D. At the centre point of the window

I cant work out how to do this question, can anyone help?

Answer 1

what do you guess?

Answer 2

I guessed A, but the answer said B

Answer 3

yep it should be B..

I used g=10 m/s^2 and calculated results for a ball dropped from 40 m..
The results show that (V1+V2)/2 (i.e 14.14 m/s) lies above center at a height of 30 m

Answer 4

Ah okay, that makes sense. Thanks.

Answer 5

welcome buddy!