Abouncy ball with a mass of 350 g is traveling at 25 m/s when it hits a wall at a 60 degree angle relative to the wall. if the ball rebounds at a 30 degree angle and traveling at 12 m/s, and impacted the wall for 0.625 seconds, what was the force that the wall exerted on the ball?

8.8 N

Explanation:

Impulse = change in momentum

In the x direction:

Fx (0.625 s) = (0.350 kg)(12 cos 30° m/s - 25 cos 60° m/s)

Fx ≈ -1.18 N

In the y direction:

Fy (0.625 s) = (0.350 kg) (12 sin 30° m/s - 25 sin 60° m/s)

Fy ≈ -8.76 N

The magnitude of the force is therefore:

F² = Fx² + Fy²

F ≈ 8.84 N

Rounded to two sig figs, the force exerted by the wall is approximately 8.8 N.

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.