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3 years ago

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john is using a pulley to lift the sail on his sailboat. the sail weighs 150N and he must lift it at 4.0m. how much work must be

done on the sail?

1 answer:

gogolik [260]3 years ago

5 0

The work done on the sail is 600 J

Explanation:

The work done to lift the sail is equal to the gain in gravitational potential energy of the sail, therefore is:

$W=mg\Delta h$

where

m is the mass of the sail

g is the acceleration of gravity

(mg) is the weight of the sail

$\Delta h$ is the change in height of the sail

In this problem we have

mg = 150 N (weight)

$\Delta h = 4.0 m$

Substituting, we find the work done:

$W=(150)(4.0)=600 J$

Learn more about work:

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022 (part 1 of 4) 10.0 points A ball is thrown vertically upward with a speed of 24.5 m/s. How high does it rise? The accelerati

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1)

Answer:

Part 1)

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Part 1)

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Part 4)

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2)

Answer:

a = 9.76 m/s/s

Explanation:

As we know that the object is released from rest

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3)

Answer:

v = 29.7 m/s

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Answer:

Part 1)

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