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3 years ago

5

Two electric motors drive two elevators of equal mass in a three-story building 10 meters tall. each elevator has a mass of 1,00

0 kg. the second elevator takes 10 seconds to do this work. calculate the power output of the second motor.

2 answers:

Licemer1 [7]3 years ago

7 0

<span>The power output is calculated by multiplying the weight of the elevator (1000 kg) by g (9.8 m/s^2) and by the distance (10 m), then dividing the product by the time (10 s). Thus, the power output of the second motor is 9800 watts.</span>

Maslowich3 years ago

5 0

Answer: The correct answer is 9800 Watt.

Explanation:

In the given problem, work done is equal to the potential energy.

The expression for the power output in the case of electric motor is as follows;

$P=\frac{mgh}{t}$ ....... (1)

here, m is the mass of the object, g is the acceleration due to gravity, h is the height and t is the time taken.

Calculate the power output of the second motor by using equation (1).

Put m= 1000 kg, g= 9.8 meter per second square, h= 10 m and t= 10 s.

$P=\frac{(1000)(9.8)(10)}{10}$

$P=9800 Watt$

Therefore, the power output of the second motor is 9800 Watt.

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$v_{fx}=1.668\ m.s^{-1}$

c)

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$v_{fy}=1.85\ sin 25.62^{\circ}$

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