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## Homework Statement

Hi I am taking a grade 11 physics correspondance course and would like to know if iam on the right track. thanks in advance.

1. (a) A force of 280 N is required to push a box 8.2 m across a rough floor. How much work is done?

(b) Explain 1 transformation of energy that occured in part a.

(e) It is found that 1.50 X 10 ^3 J of work are required to push a box across a floor a horizontal distance of 8.0 m . What average force is being exerted on the box?

## Homework Equations

W = F X D

## The Attempt at a Solution

(a) W= F X D

=280 N X 8.2 m

=2296 J

=2.2 X 10 ^3

(b) A force is provding energy that will be everntually transformed into heat energy through friciton between the force and the rough floor. The force is acting against the force of friciton.

(c) there is no work being done. This is becuase conditions for work are quite specfic and in this problem a displacement occurs but the force being exerted does not cause the displacement.

(d) W = F X D cos (theta)

=104 n X 5.0 m X cos 32 degrees

=440.99 J

=441 J

(e) F = W/ D

=150 J / 8.0 m = 18.75 N

Thanks

Pharm 89