A boy weighing 350N runs up a flight of stairs consisting of 20 steps each 10 cm high in 10 seconds.what is his power?

Power=mgh/t power=350*0.2*10/10 Power=70W,note:we can not use gravity because his weight was given

My ans is 75W

The answer is 75W

power=work/time=350*20*.1/10=.2*350= 70Watts

pisaaaa

How is it 75watts? My own is 70

350N ×20×10 /100

35×20
=700
700/200
=3.5J/S