Answer:
the lowest velocity which a body must have in order to escape the gravitational attraction of a particular planet or other object.
Explanation:
Its a sinkhole. -----------
We will apply the equation:
2as = v² - u²
v = √(2as + u²)
v = √(2 x 4 x 400 + 13²)
v = 58 m/s
Answer:
The velocity of the ball when its hit the ground will be 54.22 m/sec
Explanation:
We have given height from which ball is dropped h = 150 m
Acceleration due to gravity 
As the ball is dropped so initial velocity will be zero so u = 0 m/sec
According to third equation of motion we know that 


So the velocity of the ball when its hit the ground will be 54.22 m/sec