Kenny klutz drops his physics book off his aunt's high-rise balcony. it hits the ground below 1.5 s later?

a. with what speed does it hit?

b. how high is the balcony? ignore air drag.

Gravity causes a falling object to fall 9.8 m/s faster every second it falls.

Kenny's book started out with no speed when it was dropped.

1.5 sec later, it was falling at (9.8 x 1.5) = 14.7 m/s.

During the fall, its average speed was 1/2 (0 + 14.7) = 7.35 m/s.

Distance it covered = (average speed) x (time) =

(7.35 m/s) x (1.5 sec) = 11.025 m