Chapter 2, Problem 54R

To determine

To Find:The mass of the car.

Answer to Problem 54R

The mass of the car is $1500\text{kg}$ .

Explanation of Solution

Given:

Speed of the car is $30\text{m/s}$

Momentum of the car is $45,000\text{kg}\text{m/s}$

Formula:

Moment of an object is given by

  $\text{P}\text{=}\text{mv}$  ...... (1)

Here, $\text{P}$ is the momentum, $\text{m}$ is the mass and $v$ is the velocity.

Calculation:

Substitute the values $30\text{m/s}$ for $\text{v}$ and $45,000\text{kg}\text{m/s}$ for $\text{P}$ in equation (1)

  $\begin{array}{c}\text{P}\text{=}\text{mv}\\ \text{45000}\text{=}\text{m}\text{30}\\ \text{m =}\frac{45000}{30}\\ =1500\text{kg}\end{array}$

Conclusion:

Hence, the mass of the car is $1500\text{kg}$ .