Answer:
3 seconds
Explanation:
Height(S) of tree = 45m
Acceleration due to gravity (g) = 10m/s^2
From second equation of motion:
S = ut + 0.5at^2
Where:
u = initial velocity ; t = time taken ; a = acceleration due to gravity; S = distance or height
Here u = 0
S = ut + 0.5at^2
Plugging our values :
45 = 0(t) + 0.5(10)(t^2)
45 = 0 + 5t^2
5t^2 = 45
t^2 = 45 / 5
t^2 = 9
Taking the square root of both sides
t = 3s
