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3 years ago

11

A 73.0 kg firefighter climbs a flight of stairs 9.0 m high. how much work is required? j

1 answer:

pshichka [43]3 years ago

7 0

The strength of the fireman in vertical direction will be given by F = m * g. Then, the work done will be given by definition by W = F * d. Substituting the expression of the Force in that of the work, we have that the work will be W = m * g * d. Substituting the given values and assuming that g = 10m / s ^ 2, we have a total work of W = (73) * (10) * (9) = 6570 J

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antoniya [11.8K]

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Explanation:

There is only one force acting on the skier in the horizontal direction, and it is the force of friction, whose magnitude is

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$g=9.8 m/s^2$ is the acceleration of gravity

The negative sign is due to the fact that the direction of the force of friction is opposite to the direction of motion of the skier.

According to Newton's second law, the net force acting on the skier is equal to the product between his mass and his acceleration, so we can write:

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Learn more about accelerated motion here:

brainly.com/question/9527152

brainly.com/question/11181826

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brainly.com/question/2562700

#LearnwithBrainly

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