Question

A 1-horsepower, 24-volt DC electric motor that is 80 percent efficient requires 932.5 watts. How much power will a 1-horsepower, 12-volt DC electric motor that is 75 percent efficient require?

(Note: 1 horsepower = 746 watts)

A. 932.5 watts.
B. 1,305.5 watts.
C. 994.6 watts.

Answer 1

The power required by a 1-horsepower, 12-volt DC electric motor that is 75 percent efficient is 994.6 watts, calculated using the formula Pin = Pout / Efficiency.

Step-by-step explanation:

When calculating the power required by a 1-horsepower, 12-volt DC electric motor that is 75 percent efficient, we have to consider the actual output power and the efficiency of the motor. The formula to calculate the power required (Pin) is Pout / Efficiency, where Pout is the output power and Efficiency is the efficiency of the motor as a decimal.

First, we know 1 horsepower is equivalent to 746 watts. Given this, a 1-horsepower motor has an output power (Pout) of 746 watts. Now, for a motor that is 75% efficient, its efficiency as a decimal is 0.75.

Using the formula:

Pin = Pout / Efficiency = 746 W / 0.75 = 994.6 watts

The power required by 1-horsepower, 12-volt electric motor that is 75 percent efficient is therefore 994.6 watts.