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bearhunter [10]

3 years ago

10

A man pushes a lawn mower on a level lawn with a force of 195 N. If 37% of this force is directed downward, how much work is don

e by the man in pushing the mower 5.7 m?

1 answer:

densk [106]3 years ago

7 0

Answer:

$W = 1032.6 J$

Explanation:

Net force by which man push the lawn mower is given as

$F = 195 N$

now it is given that 37% of this force is vertically downwards

so we will have

$F_y = 0.37 \times 195$

$F_y = 72.15 N$

now we also know that

$F_x^2 + F_y^2 = F^2$

here we have

$F_x^2 + 72.15^2 = 195^2$

$F_x = 181.2 N$

Now work done by this force to move the lawn mower is given as

$W = F_x . d$

$W = (181.2)(5.7 m)$

$W = 1032.6 J$

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