Answer to Question #825 in Mechanics | Relativity for Jordan
A rock is dropped from a cliff. Approximately how long does it take to fall 45m if the acceleration due to gravity is 9.8 m/sec^2?
From the equations of the motion
h=h0 + v0t +at2/2:
h0 = gt2/2;
5 = 9.8 t2 /2;
t = sqrt (9.18) = 3.03 sec.
Answer: It will take 3 sec to fall.