A stone was dropped from the top of a building 40m high. Find, correct to one decimal place, the time it took the stone to reach the ground. [Take g = 9.8ms\(^{-2}\)]

ella51

4 years ago

Using S=ut + 1/2gt²
u= 0 and g=9.8m/s², S=40m
So, S=1/2gt²
40 =1/2 × 9.8 ×t²
40/4.9=4.9t²/4.9
t²=8.1633
t=√8.1633
t=2.857s
t=2.9s to 1d.p