Question

a 20 g ball of clay traveling east at 2.0 m/s collides with a 30 g ball of clay traveling 30m degrees south of west at 1.0 m/s. what are the speed and direction of the resulting 50 g of clay?

Answer 1

Resolve each velocity into the east and north components.
Apply the law of conservation of momentum in each direction before and after impact:
m1u1+m2u2 = (m1+m2)v
Calculate the resultant from the two directions by:
V=√(vx²+vy²)

Answer 2

A ball is dropped from rest from the top of a building and strikes the ground with the speed Vf. From ground level, a second ball is thrown straight upward at the same instant that the first ball is dropped. The initial speed of the second ball is Vi=Vf, the same with which the first ball will eventually strike the groun. Ignoring air resistance, decide whether the balls cross paths at half the height of the building, above the halfway point, or below the halfway point.

Answer 3

4.11 m/s