Question

A particle of 10 kg is moving in a constant acceleration 2m/s2 starting from rest. What is its momentum and velocity if time is equal to 2 seconds.​

Answer 1

Given:-

• Initial velocity ,u =0m/s

• Acceleration, a = 2m/s²

• Time taken ,t = 2 s

• Mass ,m = 10kg

To Find:-

• Final velocity ,v
• Momentum, ∆P

Solution:-

Firstly we calculate the Final velocity of the particle . So by using 1st equation of motion

• v = u+at

Substitute the value we get

→ v = 0 + 2×2

→ v = 4m/s

Therefore, the Final velocity Of the particle is 4m/s

Now , we calculate the Momentum of the particles.

As we know that moment is the product of mass and velocity .

• ∆P = mv

Substitute the value we get

→ ∆P = 10×4

→ ∆P = 40 Kgm/s.

Therefore the moment of the particles is 40kgm/s.

Answer 2

m = 10 kg

a = 2m/s ^2

t = 2 sec

u = 0 m/s    (Starting from rest)

$v = ut + \frac{1}{2} at^{2}\\ v = 0 + \frac{1}{2} at^{2}\\ v = \frac{1}{2} at^{2}\\\\v = \frac{1}{2} X 2 X 2 ^{2} \\v = 2^{2}\\ v = 4 m/s$

v = 4 m/s

Also , momentum = m X v

                               = 10 X 4

                               = 40 kg m/s