Answer:
1.997s = 2.0s
Explanation:
From equation of motion,
S = ut + 1/2 gt²
u = 0 m/s
t = ?
g = 9.8 m/s²
S = 1955cm = 19.55m
19.55 = 0 + 1/2 * 9.8 * t²
19.55 * 2 = 9.8t²
t² = 19.55 * 2 / 9.8
t² = 3.987
t = (3.987)^½ (take the square root of both sides)
t = 1.997s = 2.0s