How Much Power Does a Man Generate Running Up Stairs Compared to a Light Bulb?

[invincible1]

Homework Statement

the man having the weight of 75kg is able to run up a 4.5 m high flight of stairs in 4s. determine the power generated. how long would a 100w light bulb have to burn to expend the same amount of energy?

Homework Equations

The Attempt at a Solution

I havnt done these types of questions for a while so I've forgotten, so far I've calculated the work done by weight -75*9.81 (4.50) = -3310.8
can anyone help me solve the rest pleasE?
thanks

 

[NascentOxygen]

Power = rate of doing work

 

[invincible1]

yea but i don't know how to do it

 

[NascentOxygen]

How much work is done in 4 seconds?

 

[invincible1]

power=f.v but i don't know how to get the v and f?

 

[NascentOxygen]

As you know how much work was done in 4 secs, then divide by 4 secs and you have power!

Also, don't forget work = energy

 

[invincible1]

Ok thanks