Answer:
The correct option is;
11.95
Explanation:
The given parameters are;
The height from which the rock is dropped = 700 meters
The time for the to hit the ground is given by the relation, h = u·t + 1/2·g·t²
Where;
h - The height = 700 meters
u = The initial velocity = 0
t = The time taken for the rock to cover the height, h, and hit the ground
g = The acceleration due to gravity = 9.81 m/s²
Therefore, we have by substitution,
700 = 0 × t + 1/2 × 9.81 × t²
∴ t = √(700/(1/2 × 9.81)) ≈ 11.95
The time for the rock to hit the ground, t ≈ 11.95 seconds.
