Question

DATE: 1 PAGE: GENERAL • prepare atleast five numerical question based on newton's second law of manion and law of conservation of momentum on your own a one prepared ?

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Answer 1

Answer:

sorry I find only 2 numerical

Q1. There are cars with masses 4 kg and 10 kg respectively that are at rest. A car having the mass 10 kg moves towards the east with a velocity of 5 m.s-1. Find the velocity of the car with mass 4 kg with respect to ground.

Ans: Given,

m1 = 4 kg

m2 = 10 kg

v1 = ?

v2 = 5 m.s-1

We know from the law of conservation of momentum that,

Pinitial = 0, as the cars are at rest

Pfinal = p1 + p2

Pfinal = m1.v1 + m2.v2

= 4 kg.v1 + 10 kg.5 m.s-1

Pi = Pf

0=4 kg.v1+50 kg.m.s-1

v1 = 12.5 m.s-1

Q2. Find the velocity of a bullet of mass 5 grams which is fired from a pistol of mass 1.5 kg. The recoil velocity of the pistol is 1.5 m.s-1.

Ans: Given,

Mass of bullet, m1 = 5 gram = 0.005 kg

Mass of pistol, m2 = 1.5 kg

The velocity of a bullet, v1 = ?

Recoil velocity of pistol, v2 = 1.5 m.s-1

Using law of conservation of momentum,

m1u1 + m2u2 = m1v1 + m2v2

Here, Initial velocity of the bullet, u1 = 0

Initial recoil velocity of a pistol, u2 = 0

∴ (0.005 kg)(0) + (1.5 kg)(0) = (0.005 kg)(v1) + (1.5 kg)(1.5 m.s-1)

0 = (0.005 kg)(v1)+(2.25 kg.m.s-1)

v1=-450 m.s-1

Hence, the recoil velocity of the pistol is 450 m.s-1.