You push on a 3-kg box to give it an initial speed of 5 m/s across a floor. If μ_k = 0.3, how far does the box travel before coming to a stop?

(II) A package of mass m is dropped vertically onto a horizontal conveyor belt whose speed is v=1.5m/s , and the coefficient of kinetic friction between the package and the belt is μₖ = 0.70.

(a) For how much time does the package slide on the belt (until it is at rest relative to the belt)?

(II) A package of mass m is dropped vertically onto a horizontal conveyor belt whose speed is v=1.5m/s , and the coefficient of kinetic friction between the package and the belt is μₖ = 0.70.

(b) How far does the package move during this time?

A 68-kg water skier is being accelerated by a ski boat on a flat ('glassy') lake. The coefficient of kinetic friction between the skier's skis and the water surface is μₖ = 0.25 (Fig. 5–59).

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(c) Explain why the skier's acceleration in part (b) is greater than that in part (a).

Pushing a 10-kg toolbox across the floor, you find that the box moves at a constant speed when you push horizontally with a force of 39 N. What is the coefficient of kinetic friction between the floor and the toolbox?