Question

Jack and Jill are on two different floors of their high rise office building and looking out of their respective windows. Jack sees a flower pot go past his window ledge and Jill sees the same pot go past her window ledge a little while later. The time between the two observed events was 4.6 s. Assume air resistance is negligible.
a) If the speed of the pot as it passes Jill's window is 58.0 m/s, what was its speed when Jack saw it go by?
b) What is the height between the two window ledges?

Answer 1

Answer:

a) speed when Jack sees the pot : 12.92 meters per second

b) height difference 163.115 meters

Explanation:

First to calculate te initial speed we use the acceleration formula:

a= v1-v0/t

Acceleration being gravity's acceleration (9.8 m/s^2)

v1 being the speed when Jill sees the pot

v0 when Jack sees it

and t the time between

Solving for v0 it would be

v1 - a*t = v0

replacing

$58 m/s - 9.8 m/s^2 *4.6 s = v0 = 12.92 m/s$

For the second question we use the position formula setting y0 and t0 as the position and time when jack sees the pot. (and setting the positive axis downward I.E. one meter below jack would be 1m not -1m)

The formula is

$y0 + v0*t + 1/2 g *t^2 = yt$

replacing

$0m + 12.92m/s* 4.6 s + 1/2 * 9.8 m/s^2 * (4.6 s)^2 = 163.115 m$