Question

our battery has died and your friends push your vehicle so you can kick-start the engine. You and the vehicle have a combined mass of 1600 kg. If your friends do 6000 J of work and one-third of that is dissipated by friction, how fast is your vehicle traveling?

Answer 1

Answer:2.23 m/s

Explanation:

Given

Mass of person and vehicle is $m=1600\ kg$

Total work done is $W_t=6000\ J$

Friction consumes one-third of the energy

The remaining two-third is consumed to increase the kinetic energy

$\Rightarrow \dfrac{2}{3}\times 6000=\dfrac{1}{2}\times 1600\times v^2\\\\\Rightarrow 4000\times 2=1600\times v^2\\\\\Rightarrow v=\sqrt{5}\ \approx 2.23\ m/s$