Question

A car of mass 1385 kg accelerates from rest to 20.2 m/s in 6.85 s. How much force was required to do this?

Answer 1

Given

Mass of the car, m=1385 kg

The velocity, v=20.2 m/s

Time taken is t=6.85 s

To find

The force acting

Explanation

The acceleration is:

$\begin{gathered} a=\frac{v}{t} \\ \Rightarrow a=\frac{20.2}{6.85} \\ \Rightarrow a=2.94\text{ m/s}^2 \end{gathered}$

The force is

$\begin{gathered} F=ma \\ \Rightarrow F=1385\times2.94 \\ \Rightarrow F=4071.9\text{ N} \end{gathered}$

Conclusion

The force is 4071.9 N