**A basketball has a mass of 577 g. Moving to the right and heading downward at an angle of 28° to the vertical, it hits the floor with a speed of 4 m/s and bounces up with nearly the same speed, again moving to the right at an angle of 28° to the vertical. What was the momentum change Δp?**

**(Take the +x axis to be to the right and the +y axis to be up. Express your answer in vector form.)**

**Answer:**

Mass (M) = 0.577 kg

Velocity before hitting the floor (u) = 4*sin(28) x + (-4) cos(28) y*cos(28) y

Velocity after hitting the floor (v) = 4sin(28) x + 4

Change in velocity (Δv) = v-u = 0 x + 8

*cos(28) y*

Change in momentum (Δp) = MΔv

Change in momentum (Δp) = M

Δp = 0.577

*8*cos(28) y

Δp = 4.075 kg*m/s y (in upward direction only)