A bullet (W1 = 2.5 oz) with a is fired horizontally with a velocity v1 = 1675 ft/sec into the block (W2 = 6.1 lb) of soft wood initially at rest on the horizontal surface. The bullet emerges from the block with the velocity v2 = 1195 ft/sec, and the block is observed to slide a distance of d = 8.9 ft before coming to rest. Determine the coefficient of kinetic friction μk between the block and the supporting surface.

An alligator swims to the left with a constant velocity of 5 \,\dfrac{\text{m}}{\text s}5 s m ? 5, space, start fraction, m, divided by, s, end fraction. when the alligator sees a bird straight ahead, the alligator speeds up with a constant acceleration of 3 \,\dfrac{\text {m}}{\text s^2}3 s 2 m ? 3, space, start fraction, m, divided by, s, start superscript, 2, end superscript, end fraction leftward until it reaches a final velocity of 35 \,\dfrac{\text {m}}{\text s}35 s m ? 35, space, start fraction, m, divided by, s, end fraction leftward. how many seconds does it take the alligator to speed up from 5 \,\dfrac{\text {m}}{\text s}5 s m ? 5, space, start fraction, m, divided by, s, end fraction to 35 \,\dfrac{\text {m}}{\text s}35 s m ? 35, space, start fraction, m, divided by, s, end fraction?

What is the weight of a feather (mass = 0.0001 kg) that floats through earth's and the moon's atmospheres?

What is friction? how does it affect the motion of an object?