Question

A man weighing 60kg runs up 30steps in the staircase each of 20cm high in 20seconds. Calculate the work done by the man and it's power (g=10m/s)

Answer 1

M=60kg     g=10m/s

F=60*10

 =600N

S=30*20

 =600cm

 =6m

t=20s

W=F*S

  =600*6

  =3600J

P=W/t

 =3600/20

 =180W

Answer 2

Force = mass× acceleration due to gravity

Force = 60× 10=600newton

Displacement = 30×20=600cm =6m

Work done=600×6=3600joule(force ×displacement)

Power=work done/time =3600/20watt

=180watt