Question

An engine performs 2700 J of work on a scooter. The scooter and rider have a combined mass of 150 kg. If the scooter started at rest, what is the speed of the bike after the work is performed?

Answer 1

Due to the principle of conservation of energy, the work done by the engine to move the scooter converts into kinetic energy of the scooter:
$W=K= \frac{1}{2} M v^2$
where M is the combined mass of scooter and rider, and v is the velocity of the scooter. Therefore, we can find the velocity as:
$v= \sqrt{ \frac{2W}{M} } = \sqrt{ \frac{2\cdot 2700 J}{150 Kg} }=6 m/s$