Question

A penny is dropped from the top of the Empire State Building in New York City (h=381 m). Knowing that gravity accelerates the penny at a rate of –9.8 m/s 2 , with what velocity does the penny hit the ground? How long does it take to hit the ground?

Answer 1

Explanation:

v²-u² = -2gs

v²-0 = -2*9.8*381

v = 86.5m/s

.

t

v=u-gt

86.5 = 0-9.8t

|t|= 86.5/9.8 = 8.83s