Question

A cargo lift absorbs 50,000 J of energy during one morning shift, but the work performed is 40,000 J. Calculate the energy that has been lost and also the lifts performance.

Answer 1

Respuesta:

P = W : T

1day = 24h ----->the morning = 12h = 12·3,600 = 43,200s

ENERGY LOST

Ptotal = P useful + P lost

P lost = P total- P useful---> 50,000J- 40,000J = 10,000J

Solution : 10.000J of energy lost

LIFT´S PERFORMANCE

n= P useful/P total · 100 = 40,000/ 50,000J · 100 = 80%