Question

A 1.00 x 109 kg object is raised vertically at a

constant velocity of 4.00 m/s by a crane. What
is the power output of the crane?

Answer 1

P = 3.92 10¹⁰ W

Step-by-step explanation:

The power is data by the expression

P = W / t

the work of a force is

W = F. y

the bold ones represent vectors. In this case the displacement is vertical upwards and the vertical forces upwards, therefore the angle is zero and the cos 0 = 1

W = F y

we substitute

P = F y / t

P = F v

as the body rises at constant speed the acceleration is zero and from the equilibrium condition

F -W = 0

F = mg

we substitute

P = m g v

let's calculate

P 1.00 10⁹ 9.8 4

P = 3.92 10¹⁰ W