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elena-s [515]
3 years ago
13

A 4 kW vacuum cleaner is powered by an electric motor whose efficiency is 90%. (Note that the electric motor delivers 4 W of net

mechanical power to the fan of the cleaner). What is rate at which this vacuum cleaner supplies energy to the room when running
Physics
1 answer:
RoseWind [281]3 years ago
3 0

Answer:3.6\ kW

Explanation:

Given

Power Supplied [tex]P_{input}=4\ kW[/tex]

Efficiency of the motor \neta =90\%

and \neta =\dfrac{\text{Power output}}{\text{Power input}}

\Rightarrow 0.9=\dfrac{P_{out}}{4}

\Rightarrow P=0.9\times 4

\Rightarrow P=3.6\ kW

So, vacuum cleaner delivers a power of 3.6\ kW

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