6) Joe throws a 0.15-kg rubber ball directly downward to the floor. The ball’s speed just before impact is 6.5 m/s and just after the impact is 3.5 m/s. If the ball is in contact with the floor for 0.025 s, what is the magnitude of the average force that the floor exerts on the ball during the time of contact? A. 133 N B. 60 N C. 30 N D. 18 N E. 3.0 N

B. 60 N

Explanation:

Change in momentum after ball bounces back = m ( v - u )

v is velocity after the bounce and u is before the bounce

= .15 ( 6.5 + 3.5 )

1.5 kg m /s

If F be the average force acting on the ball which changed its velocity

impulse of force = force x time

= F x .025

Impulse of force = change in momentum

F x .025  = 1.5

F = 1.5 / .025

= 60 N .

the answer is ampere

the ampere is used to measure electricity. an ampere is a unit of electric current equal. a unit of measure for the flow of current in a circuit. one ampere is the amount of current flow provided when one volt of electrical pressure is applied against one ohm of resistance.