Given data:
* The mass of the car before cutting the spring is m_1 = 800 kg.
* The speed of the car before cutting the spring is u = 12 m/s.
* The mass of the car after cutting the spring is m_2 = 900 kg.
Solution:
According to the law of conservation of momentum, the momentum of the car remain conserved before and after cutting the spring,
[tex]m_1u=m_2v[/tex]
where v is the final velocity of the car after cutting the spring,
Substituting the known values,
[tex]\begin{gathered} 800\times12=900\times v \\ v=\frac{800\times12}{900} \\ v=\frac{9600}{900} \\ v=10.66667\text{ m/s} \end{gathered}[/tex]
Thus, the speed of a 900 kg car is approximately 10.67 m/s.
The momentum of 900 kg car is,
[tex]\begin{gathered} p=m_2v \\ p=900\times10.66667 \\ p\approx9600\text{ kgm/s} \end{gathered}[/tex]
Thus, the momentum of the 900 kg car is 9600 kgm/s.
