Question

a)If you roll a putty ball around inside of a bowl, it soon comes to a rest in the center. A steel ball will orbit quite a few times before coming to rest in the center of the bowl. What would be the ideal motion of the ball in the bowl? (no friction)

b) A car can accelerate by 3m/sec^2. What is its accleration if it is twoin another car like itself?

c)A skate boarder weighing 80lbs rides a 6lb skateboard down a 12 degree(from the horizontal) hill at a constant velocity. what is the force of friction acting on the board?

thank you for your time, i really appreciate it:) please help!!!

Answer 1

No friction? it loses no speed. It must travel in like an orbit forever.

If mass is doubled and the pulling force is the same...
F=Ma

The force down the hill is (86)sinTheta
if it is at constant speed, the friction must be equal and opposite.

Answer 2

thanks sooo much:)