Question

a 5.2 - kg ball rolling at 2.5 m/s bumps into a pillow and stops in 0.60 s. part a find the force exerted by the pillow. express your answer to two significant figures and include the appropriate units. f = value units

Explanation:

Step1: Identify the formula

We use the impulse - momentum theorem $F\Delta t=\Delta p = m(v_f - v_i)$. Here, $v_f = 0$ (the ball stops), $m = 5.2$ kg, $v_i=2.5$ m/s and $\Delta t = 0.60$ s.

Step2: Calculate the change in momentum

$\Delta p=m(v_f - v_i)=5.2\times(0 - 2.5)=- 13$ kg·m/s.

Step3: Solve for the force

From $F\Delta t=\Delta p$, we can express $F=\frac{\Delta p}{\Delta t}$. Substituting the values, $F=\frac{-13}{0.60}\approx - 22$ N. The negative sign indicates the force is in the opposite direction of the ball's initial motion.

Answer:

$F = 22$ N