Question

A man throws a ball weighting 100g vertically upwards with a speed of20m/s. What will be its initial momentem? What would be its mamentum at the highest point

Answer 1

Answer:

Initial momentum of ball is 2 kg m / sec .  

At highest point momentum is  0 kg m / sec .

Explanation:

Given :

Mass of ball m is 100 g  or 0.1 kg

Velocity of ball is 20 m / sec

We know that momentum is nothing but product of mass and

velocity .

i.e.  p = m v

Putting values here we get

p = 0.1 × 20 kg m / sec .

p = 2 kg m / sec .

Thus initial momentum of ball is 2 kg m / sec

At highest point velocity will be 0 m / sec

So momentum at the highest point will be

p = m × 0 kg m / sec

p = 0 kg m / sec

At highest point momentum is  0 .

Hence we get answer .

Answer 2

$\huge\underline\mathfrak\blue{Answer}$

The initial momentum when ball is thrown is 2 kg.m/s.

The momentum at the highest point is 0 kg.m/s.

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$\huge\underline\mathfrak\blue{Explanation}$

Given : Mass of ball = 100g = 0.1 kg

initial velocity (u) = 20 m/s

To find :

• Initial momentum when ball is thrown.
• Momentum at the highest point.

Solution : We know that,

Momentum = mass × velocity

Therefore, initial momentum = mass × initial velocity

Initial momentum = 0.1 × 20

Initial momentum = 2 kg.m/s

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Now,

Momentum at the highest point = mass × final velocity

but final velocity (v) = 0 ( as the ball thrown vertically upward )

Momentum at the highest point = 0.1 × 0

Hence, the momentum at the highest point = 0 kg.m/s

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