Question

A stone is dropped into water from a bridge 52 m above the water's
surface. What can be determined about the stone as it reaches the
water?

Answer 1

Answer:

Its final velocity and how much time it takes to reach the water

Explanation:

The motion of the stone is a uniformly accelerated motion, so we can use the following suvat equation to determine its final velocity:

$v^2-u^2=2as$

where

v is the final velocity

u = 0 is the initial velocity

$a=g=9.8 m/s^2$ is the acceleration of gravity

s = 52 m is the distance covered during the fall

Solving for v,

$v=\sqrt{u^2+2as}=\sqrt{0^2+2(9.8)(52)}=31.9 m/s$

We can also find how much time it takes to reach the water, using the equation

$v=u+at$

where

v = 31.9 m/s is the final velocity

u = 0 is the initial velocity

$a=g=9.8 m/s^2$

t is the time

And solving for t,

$t=\frac{v-u}{a}=\frac{31.9-0}{9.8}=3.26 s$