A 2.90-kg block starts from rest at the top of a 30.0° incline and slides a distance of 1.70 m down the incline in 1.80 s.


(b) Find the coefficient of kinetic friction between block and plane. ________???

(c) Find the friction force acting on the block.
magnitude __________ N ????? direction up the incline.

(d) Find the speed of the block after it has slid 1.70 m.
________________m/s ????

A rifle bullet with a mass of 12.5 g traveling toward the right at 284 m/s strikes a large bag of sand and penetrates it to a depth of 24.1 cm. Determine the magnitude and direction of the friction force (assumed constant) that acts on the bullet.

magnitude _________N?????
direction is to the left


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