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3 years ago

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A gardener pushes a wheelbarrow around the edges of a lawn. When she has finished, she is 5 m from her starting point. She has t

o pull upwards with a force of 300 N to lift the legs of the wheelbarrow off the ground. She pushes the wheelbarrow along the ground with a force of 100 N. Calculate how much work the gardener does in pushing the wheelbarrow around the lawn.

1 answer:

zvonat [6]3 years ago

3 0

Answer:

Work done by the gardner is 500 J

Explanation:

As we know that the gardner apply force perpendicular upward by magnitude 300 N and along the floor horizontal force is 100 N

so we have

$F = 100 \hat i + 300 \hat j$

now the displacement of the gardner along the floor is

$d = 5\hat i$

now work done is given as

$W = F. d$

so we have

$W = (100 \hat i + 300 \hat j). (5\hat i)$

$W = 500 J$

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