Question

pre - and post - collision information is shown. identify the collision parameters that are consistent with the indicated change in momentum.
initial state
p = 12 kg·m/s
2 kg
collision parameters
final state
p = 4 kg·m/s
2 kg
tap an option below to select or change an answer.
(a + sign indicates a rightward direction; a - sign indicates a leftward direction.)
impulse = +2 n·s
impulse = +6 n·s
impulse = -4 n·s
impulse = -8 n·s
impulse = -16 n·s

Explanation:

Step1: Recall impulse - momentum theorem

Impulse \(J=\Delta p\), where \(\Delta p = p_f - p_i\).

Step2: Calculate the change in momentum

Given \(p_i = 12\ kg\cdot m/s\) and \(p_f=4\ kg\cdot m/s\). Then \(\Delta p=p_f - p_i=4 - 12=- 8\ kg\cdot m/s\). Since \(1\ N\cdot s = 1\ kg\cdot m/s\), the impulse \(J=-8\ N\cdot s\).

Answer:

Impulse = - 8 N·s