Question

Question 41 ptsAn object has a momentum of 100 kg m/s. What impulse is needed to stop it from moving?O 100 kg m/s50 kg m/sO 200 kg m/sO 1000 kg m/s1 ptsQuestion 5

Answer 1

100 kg m/s

Explanation

Step 1

Momentum is defined as the amount of motion occurring in something that is moving, or the force that drives something forward to keep it moving.

$\begin{gathered} \rho=mv \\ \rho\text{ is the momemtum} \\ m\text{ is the mass} \\ v\text{ is the velocity} \end{gathered}$

and impulse is the measure of how much the force changes the momentum of an object

$Impulse=\Delta\rho=P_{final}-P_{initial}$

so

a)let

$\begin{gathered} \rho_1=100\text{ kg}\frac{m}{s} \\ stop\text{ moving the object indicates velocity=0,so} \\ \rho_2=m*v_2=m*0=0 \\ Impluse=I \end{gathered}$

b) now, replace

$\begin{gathered} Impulse=\Delta\rho=P_{final}-P_{initial} \\ Impluse=0-100kg\frac{m}{s} \\ Impulse=-100\text{ kg}\frac{m}{s} \\ the\text{ negative indicates the impulse is in the opposite direction to the velocity} \end{gathered}$

so,the answer is

100 kg m/s

I hope this helps you