Polly is pushing a box across the floor with a force of 30 n. the force of gravity is –8 n, and the normal force is 8 n. which value could describe the force of friction if polly could not move the box?

The value of the friction that would describe the system would be the same as the pushing force Polly gives to the box which is 30 N. This is because the forces should be balanced out  in the x-direction and in the y-direction since the box was not moved.

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