Question

A ball is dropped from a height of 5m. Find the velocity of the ball just before it reaches the ground. Do you require the value of mass to find the velocity?

Very urgent....... Pls someone Ans this fast...... Pls........

Answer 1

Use equation of motion
v² - u² = 2aS

Where
v = Final velocity of ball
u = Initial velocity of ball
a = Acceleration of ball
S = Displacement covered by ball

In this case ball is dropped. So, u = 0

Our equation will become v = √(2aS)

Now, substitute the values
v = √(2 × 10 m/s² x 5 m)
= 10 m/s

Velocity with which it hits the ground is 10 m/s
[Note: I took g = 10 m/s² to my calculations easy]
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Do you require value of mass to find the velocity?
No, we didn’t required. No matter what the mass of body is, it’s final velocity will be same neglecting the resistance offered by air.

Answer 2

Hi friend,

We can just use the formula of laws of motion,

V²-u²= 2as

Where initial velocity (u)=0

V²= 2as

V²= 2×10×5

V= 10m/s.

The ball acquires the velocity of 10m/s before Fall to the ground.

We doesn't need the mass for finding the velocity.

Hope this helped you a little!!!