Physics year 11 (1 Viewer)

[ugotkeys]

Hey i was wondering if anyone could help me with this physics question:

A battery operated toy car of mass 0.5kg is moving at 5m/s before its speed is increased to 7m/s.
What is the amount of work done by the toy's engine to increase its speed?

Cheers

 

[Kurosaki]

Um, I think the work done is the kinetic energy gained. thus: final kinetic energy minus initial kinetic energy
0.5mv^2-0.5mU^2= 0.5(0.5)(49)-(0.5)(0.5)(25)=12.25-6.25=6 Joules.

Therefore 6 joules of work have been done on it =).

 

[Kurosaki]

I think that's the answer anyways....check the answers if you have them =).

 

[ugotkeys]

Thanks heaps