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3 years ago

11

A student with a weight of 784 N runs up three flights of stairs in 12.0 sec. The student has gone a vertical distance of 8.0 m.

How much work is done by the student to move his body to this height? Assume that his speed is constant.
A) 98J
B) 1176J
C) 6272J
D) 61466J

1 answer:

Lilit [14]3 years ago

7 0

Answer:

C) 6272 J

Explanation:

The work done by the student is equal to the increase in gravitational potential energy; therefore, it is given by

$W=Fd$

where

F = 784 N is the force, which in this case is equal to the weight of the student

d = 8.0 m is the vertical distance covered

Substituting numbers into the formula, we find:

$W=(784 N)(8.0 m)=6272 J$

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