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3 years ago

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A 1500-W heater is connected to a 120-V line for 2.0 hours. How much heat energy is produced?

1 answer:

weeeeeb [17]3 years ago

3 0

<span>A joule is equal to one watt per second and so we must find out how many seconds are in two hours. A shortcut you can use is remove the zeros and multiplying the remaining numbers before adding the the zeros back to the total of your result 6 x 6 x 2 = 72 and thus 60 x 60 x 2 = 7200 72 x 15 = 1080 and thus 7200 x 1500 = 10800000 joules one mega joule equals one million joules So we can simplify things and say 10.8 MJ</span>

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elena-s [515]

First of all, we need to convert the angular speed from rev/min into rev/s:

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The angular acceleration is the variation of angular speed divided by the time:

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And this is constant, so we can use the following equation to calculate the angle through which the engine has rotated:

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sleet_krkn [62]

Answer:

$\alpha=78.4\ rad.s^{-2}$

Explanation:

Given:

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diameter of cylinder, $d=0.25\ m$

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Answer:

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