A diving bell is lowered into the sea at a speed of 6m/s and comes to rest with uniform retardation at a distance of 20m below the surface. What is it's retardation?

Answer 1

What you are calling retardation is usually called deceleration. Let its value be a.

Vo = sqrt(2 a X)

X = 20 m
Vo = initial velocity = 6 m/s

6 = sqrt(2*a*20)
36 = 40 a
a = 0.9 m/s^2