Question

A 3730-kg SUV can climb up a 600-m high hill in one minute (60 seconds). How much is its power output in horse-powers? 245 hp

490 hp
800 hp
373 hp
600 hp

Answer 1

490hp

Step-by-step explanation:

Power is energy per unit of time, an in this case the energy needed is the gravitational potential energy, so we have:

`P=E/t=mgh/t=(3730kg)(9.8m/s)(600m)/60s=365540W`

Since all units are in S.I. we get our result in Watts (Joules/s). To convert to horse power (imperial), we need to know that:

`745.7 W = 1 hp`

Which obviously means:

`(1 hp)/(745.7 W) = 1`

So we can write:

`P=365540W=365540W((1 hp_m)/(745.7 W))=490hp`

There is also metric horse power (
`735.5 W = 1 hp`), and using this value we get
`P=497hp`, although both results are close.