Question

Calculate the amount of power (in Watts) required to move an object weighing 762 N from point A to point B within 29 seconds. Distance between point A and point B is 5.0 meters and they are at the same level. (Ignore the frictional losses)

Answer 1

Answer:

0.556 Watts

Explanation:

w = Weight of object = 762 N

s = Distance = 5 m

t = Time taken = 29 seconds

a = Acceleration

g = Acceleration due to gravity = 9.81 m/s²

Equation of motion

$s=ut+\frac{1}{2}at^2\\\Rightarrow a=\frac{2\times (s-ut)}{t^2}\\\Rightarrow a=\frac{2\times (5-0)}{29^2}=\frac{10}{481}$

Mass of the body

$m=\frac{w}{g}=\frac{762}{9.81}$

Force required to move the body

$F=ma\\\Righarrow F=\frac{762}{9.81}\times \frac{10}{481}$

Velocity of object

$v=u+at\\\Rightarrow v=0+\frac{10}{481}\times 29\\\Rightarrow v=\frac{10}{29}$

Power

$P=Fv\\\Rightarrow P=\frac{762}{9.81}\times \frac{10}{481}\times \frac{10}{29}=0.556\ W$

∴ Amount of power required to move the object is 0.556 Watts