Imagine a raindrop starting from rest in a cloud 2 km in the air. if it fell with no air friction at all, it would accelerate toward the ground with gravitational acceleration of 9.8m/s2. what would the speed of the drop be when it reached the ground? convert your answer into miles per hour.
1) 212 mph
2) 433 mph
3) 774 mph
4) 72.5 mph

2) 433 mph

Explanation:

The final velocity of the raindrop as it reaches the ground can be found by using the equation for a uniformly accelerated motion:

where

v is the final velocity

u = 0 is the initial velocity (the raindrop starts from rest)

a = g = 9.8 m/s^2 is the acceleration due to gravity

d = 2 km = 2000 m is the distance covered

Solving for v,

And keeping in mind that

1 mile = 1609 metres

1 hour = 3600 s

The speed converted into miles per hour is

can be answered using momentum.

momentum = p

p1= mass1 * velocity1

p1 = p2

therefore

p1 = 6kg * 4m/s

p1 = 24kgm/s

p2=m2 * v2

24 kgm/s = 7kg * v2

v2 = 24 kgm/s / 7kg

v2= 3.42 m/s

the displacement produced by the body.  

the amount of force subjected to the body.  

the angle between the direction of force and displacement