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2 years ago

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A person who climbs up something (e.g., a hill, a ladder, the stairs) from the ground gains potential energy. a person's weight

(f = mg) is usually measured in pounds. for conversions, you may need to know that the weight of 1 pound is equal to 4.448 newtons. part a how many meters above the ground would a 240 lb person have to climb to gain 3 kilojoules (3000 joules) of potential energy?

1 answer:

zhannawk [14.2K]2 years ago

3 0

We are given the following values:

weight w = 240 lb = 1,067.52 N

energy E = 3,000 J

The formula for potential energy is:

E = w h

where h is the height the person has to climb, therefore:

h = 3000 / 1067.52

<span>h = 2.81 m</span>

<span>
</span>

<span>Therefore he has to climb 2.81 meters</span>

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When the ball has left your hand and is flying on its own, its kinetic energy is

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Explanation:

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For 3 kg can

$T-3g=3a$

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From 1 and 2

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$a=\frac{g}{7}$

So time taken to cover 18 m is

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