Question

Question:
A 65 kg girl is driving a 535kg car at a constant velocity of 11.5 m/s. calculate the momentum of girl- car system. ​

Answer 1

Answer:

6,152.5 kgm/s

Explanation:

momentum(p)= mass × velocity

⇒p= 535kg × 11.5m/s

⇒p=6,152.5 kgm/s.

Answer 2

According to the question, we know that the girl and the car are both systems as they move together as a single unit. So now, we need to find the total mass of the system.

$m_T=m_g+m_s$

$65kg+535kg$

$600kg$

Now, the momentum of the system is in the same direction as the velocity of the system. Now we need to use the scalar of $\vec{p} = m \vec{v}$ to find the correct magnitude of the momentum.

$p=m_Tv$

$600kg\times 11.5m/s$

$6.9\times 10^{3}kg\cdot m/s$

∴ The momentum of the girl  - car system is $6.9\times 10^{3}kg\cdot m/s$.