# Varying coefficient of friction

A box is sliding with a speed of 4.50 m/s on a horizontal surface, when at point P, it encounters a rough section. On the rough section, the coefficient of friction is not constant, but starts at 0.100 at P and increases linearly with distance past P, reaching a value of 0.600 at 12.5 m past point P.

a) use the work-energy theorem to find how far this box slides before stopping.

b) what is the coefficient of friction at the stopping point?

c) how far would the box have slid if the friction coefficient didn't increase, but instead had the constant value of 0.100?

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#### Solution Preview

A box is sliding with a speed of 4.50 m/s on a horizontal surface, when at point P, it encounters a rough section. On the rough section, the coefficient of friction is not constant, but starts at 0.100 at P and increases linearly with distance past P, reaching a value of 0.600 at 12.5 m past point P.

a) use the work-energy theorem to find how far this box ...

#### Solution Summary

A calculation of a sliding box on a horizontal surface and calculating the coefficient of friction.