Answer:
2 seconds
Explanation:
From the question,
Applying the equation of motion for a body falling under gravity
s = ut+1/2gt²................................. Equation 1
Where, s = hieght of fall, u = initial velocity, t = time, g = acceleration due to gravity.
Given: s = 20 m, u = 0 m/s, t = ?, g = 10 m/s²
Substitute these values into equation 1
10 = 0(t²)+1/2(10×t)
10 = 5t
Solve for t
5t/5 = 10/5
t = 2 seconds
