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8090 [49]
3 years ago
14

A person struggles very hard to lift a large boulder. He puts in so much effort, he starts to sweat, his heart rate increases, a

nd he gets really tired. All of his effort is for nothing, the boulder does not move at all. In this situation, has work been done? Explain!
*Use the scientific definition of "work" to answer this question.
Physics
1 answer:
Lesechka [4]3 years ago
5 0
No, he did not perform any work. Work is when you’re using energy which results in a force. Even though he was tired and sweaty, he did not move the boulder. So therefore he did not perform any work.
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Answer:

<h2>f=a×m</h2>

m=1800kg

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8 0
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A swan on a lake gets airborne by flapping its wings and running on top of the water. If the swan must reach a velocity of 6.40
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Answer:

53.895 m.

Explanation:

Using the equation of motion,

v² = u² + 2as .............. Equation 1

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make s the subject of the equation,

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Given: v = 6.4 m/s, u = 0 m/s ( from rest)  a = 0.380 m/s².

Substitute into equation 2

s = (6.4²-0²)/(2×0.380)

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3 years ago
The total amount of force exerted on an object is called
ziro4ka [17]

Answer:

net force

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7 0
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A bike with 15cm diameter wheels accelerates uniformly from rest to a speed of 7.1m/s over a distance of 35.4m. Determine the an
Finger [1]

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iogann1982 [59]

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Explanation:

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