If a fly collides with the wind shield of fast moving bus ,which object experiences an impact force with a larger magnitude ?

Tall pacific coast redwood trees can reach heights of about 100 m. if air drag is negligibly small, how fast is a sequola cone moving when it reaches the ground f it dropped from the top of a 100 m tree?

Calculate a pendulums frequency of oscillation (in hz) if the pendulum completes one cycle in 0.5s.

The ima of the following pulley system is