A pencil case is dropped vertically from a height at rest and hits the ground 0.5 seconds later a) What vertical velocity did the pencil case hit the ground with?

b) What horizontal velocity did the pencil case hit the ground with?

Identify the correct relation showing that the radius r of the orbit of a moon of a given planet can be determined from the radius r of the planet, the acceleration of gravity at the surface of the planet, and the time τ required by the moon to complete one full revolution about the planet. determine the acceleration of gravity at the surface of the planet jupiter knowing that r = 71 492 km and that t= 3.551 days and r= 670.9 × 10^3 km for its moon europa.