Question

2 - 4 mastery check: impulse - momentum equation
version a
pass □
revise □

1. complete the table.
2. kit the cat (5 kg) is running at 12 m/s when she starts sliding across a

smooth floor. friction provides a 20 n stopping force.

• what is kits change in momentum?

show your work.

Explanation:

Step1: Recall the impulse - momentum theorem

The impulse - momentum theorem states that the impulse \(I\) (or \(J\)) is equal to the change in momentum \(\Delta p\). The formula is \(I = F\times\Delta t=\Delta p = m\times\Delta v\).

Step2: Identify the given values

We know that the force \(F = 20\space N\). But we can also use the fact that the initial velocity \(u = 12\space m/s\) and the final velocity \(v=0\space m/s\) (since the cat stops), and the mass \(m = 5\space kg\).

Step3: Calculate the change in momentum using \(\Delta p=m\times\Delta v\)

The change in velocity \(\Delta v=v - u=0 - 12=- 12\space m/s\). Then \(\Delta p=m\times\Delta v\). Substitute \(m = 5\space kg\) and \(\Delta v=-12\space m/s\) into the formula: \(\Delta p=5\times(- 12)=-60\space kg\cdot m/s\). The magnitude of the change in momentum is \(60\space kg\cdot m/s\).

Answer:

The change in Kit's momentum is \(60\space kg\cdot m/s\)