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Elza [17]
4 years ago
15

the useful power out of an electric motor is 20w and the total power into the motor is 80w calculate the percentage efficiency o

f the motor
Physics
1 answer:
olganol [36]4 years ago
4 0

Answer:

25%

Explanation:

Efficiency is the ratio of power out to power in.

e = 20 W / 80 W

e = 0.25

The motor is 25% efficient.

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Which of the following distinguishes the isotope uranium-238 from the isotope uranium-235?
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Explanation:

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Answer:

<h2>3.36J</h2>

Explanation:

Step one:

given data

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assume g= 9.81m/s^2

we know that work done= force *distance moved

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Step two:

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<h2>Answer: about the same size of the gap  or slit</h2>

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Note that the principal condition for the occurrence of this phenomena is that the obstacle must be comparable in size (similar size) to the size of the wavelength.

In other words, when the gap (or slit) size is larger than the wavelength, the wave passes through the gap and does not spread out much on the other side, but when the gap size is equal to the wavelength, maximum diffraction occurs.

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<u />

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have a good day :)

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