Question

3.A stone of mass 3kg is moving at a velocity of 10 m/s. If its velocity is increased to 30 m/s, calculate the change in momentum.

pls give the correct answer for 2 marks​

Answer 1

GIVEN :-

• Mass of body , m = 3 kg.
• Initial velocity , u = 10 m/s.
• Final velocity , v = 30 m/s.

TO FIND :-

• The change in momentum , ∆p.

SOLUTION :-

As we know that,

➳ Final momentum = Mass × Final velocity.

➳ pf = m × v

➳ pf = 3 × 30

➳ pf = 90 kg . m/s.

Now,

➠ Initial momentum = Mass × Initial velocity.

➠ pᵢ = m × u

➠ pi = 3 × 10

➠ pi = 30 kg .m/s.

Now,

➳ Change in momentum = Final momentum - Initial momentum

➳ ∆p = pf - pi

➳ ∆p = 90 kg . m/s - 30 kg . m/s

➳ ∆p = 60 kg . m/s.

Hence the change in momentum is 60 kg . m/s.

Answer 2

Given:

A stone of mass 3kg is moving at a velocity of 10 m/s. Its velocity is increased to 30 m/s.

To find:

Change in Momentum

Calculation:

• Momentum is a vector quantity represented by the product of mass of an object and its velocity.

So, initial Momentum :

$\sf{\therefore \: P1 = m \times (v1)}$

$\sf{ = > \: P1 = 3\times 10}$

$\sf{ = > \: P1 = 30 \: kgm {s}^{ - 1} }$

So, Final Momentum:

$\sf{\therefore \: P2 = m \times (v2)}$

$\sf{ = > \: P2 = 3\times 30}$

$\sf{ = > \: P2 = 90 \: kgm {s}^{ - 1} }$

So, change in Momentum:

$\sf{\therefore \: \Delta P = P2 - P1}$

$\sf{ = > \: \Delta P = 90 - 30}$

$\sf{ = > \: \Delta P = 60 \: kgm {s}^{ - 1} }$

So, change in momentum is 60 kg m/s.