Question

A 500-kg elevator is raised to a height of 20 m in 10 seconds. Calculate the power of the motor.
A) 98,000 W
B) 9,800 W
C) 2,500 W
D) 1000 W

Answer 1

<>"power = 500 kg x 9.8 m/s² x 20 m / 10s = 9800 watts."<>

Answer 2

Answer:

Power, P =9800 W

Explanation:

It is given that,

Mass of the elevator, m = 500kg

It is raised to a height of 20 m in 10 seconds

Power is defined as the work done per unit time.

$P=\dfrac{W}{t}$

Work done is given by :

$W=mgh$

h is the height

So, $P=\dfrac{mgh}{t}$

$P=\dfrac{500\ kg\times 9.8\ m/s^2\times 20\ m}{10\ s}$

P = 9800 Watts

Hence, the power of the motor is 9800 W. The correct option is (b).