You have a 0.35 long pendulum attached to the roof inside your car. Your car is travelling at a speed of 1.0 m/s when it hits a concrete wall and stops immediately. If the pendulum is free to swing, to what maximum angle to the vertical does the pendulum swing upon impact?

Answer 1

assuming the pendulum is straight down before the impact, its KE was 1/2 m 1^2

that KE is translated to PE as it swings.

mgh=1/2 m v^2

h= 1/(2g)

angle= arccos((.35-h)/.35)