Work done climbing a flight of stairs.

fattydq

A 58 kg firefighter climbs a flight of stairs 5.3 m high. How much work is required?

I know work is just force times distance, but I'm not given a force? And I can't really find a force because force is mass times acceleration and I'm not given an acceleration...help!

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mgb_phys

Homework Helper
Do you know about gravitational potential energy?

Actually you are given a force, if he has a mass of 58kg (you must have some skinny firemen!) and he is on Earth, how much does he weigh?

fattydq

Do you know about gravitational potential energy?

Actually you are given a force, if he has a mass of 58kg (you must have some skinny firemen!) and he is on Earth, how much does he weigh?
9.8 times 58...so 568.4 N right? Then 568.4 times 5.3m and you get 3012.52, yes? Would the unit be joules?

mgb_phys

Homework Helper
Yes - but think about how many significant figures you should have

The equation for potential energy = m g h
As you said this is the same as force (mg) * distance (h)
And yes J = N m = kg m^2/s^2

fattydq

Would it just be 3.0 times 10^3 in correct sig figs?

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?????

mgb_phys

Homework Helper
Yes, you have 2 sig figures for the mass and height so it's two sig figures for the answer.
So formally 3.0 x 10^3 J or 3000J would probably be ok.

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