Question

Ms. Wilkins pushes her car with a force of 2,100 Newtons from rest to 9 m/s in 3seconds. What is the mass of her car?

Answer 1

Given data

*The given force exerted on the car is F = 2100 N

*The given initial speed of the car is u = 0 m/s

*The given final speed of the car is v = 9 m/s

*The given time is t = 3 s

The formula for the acceleration of the car is given by the first equation of motion as

`v=u+at`

Substitute the known values in the above expression as

`\begin{gathered} 9=0+a(3) \\ a=3m/s^2 \end{gathered}`

The formula for the mass of the car is given as

`\begin{gathered} F=ma \\ m=(F)/(a) \end{gathered}`

Substitute the known values in the above expression as

`\begin{gathered} m=(2100)/(3) \\ =700\text{ kg} \end{gathered}`

Hence, the mass of the car is m = 700 kg