contestada

a girl weighing 350N runs up hill upto 5m in 20sec. calculate her work done and power

Respuesta :

P=350/300+20. P=350/320. P=35/32. P=1.09

Work done against gravity becomes potential energy of the object-Earth system. Its given by:

W = Ep

W = mgh  but weigh(w) = mg

W = wh

W = 350 N × 5 m

W = 1750 J

Power is the amount of energy transferred or converted per unit time. This is:

P = W/t

P = 1750 J / 20 s

P = 87.5 W