Question

Describe momentum and law of conservation of momentum in detail with examples​

Answer 1

αиѕωєя❤:-

Conservation of momentum is a major law of physics which states that the momentum of a system is constant if no external forces are acting on the system. It is embodied in Newton's First Law or The Law of Inertia.

Answer 2

Answer:

Momentum

Momentum of a body is equal to the product of its mass and velocity.

i.e. momentum = mass × velocity or

$\bf \overrightarrow{p}\:=\:m\overrightarrow{v}$

• Momentum is a vector quantity whose direction is same as that of the velocity.

• SI unit of momentum is kg ms⁻¹ .
• Dimensional formula for momentum = [MLT⁻¹] .

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Law of Conservation of Momentum:-

According to this law, the total linear momentum of an isolated system remains constant.

Or

The total momentum of a system remains constant if no external force acts on it.

Example:

Recoil of a Gun.

When a bullet is fired from a gun, the gun recoils or the gun moves backwards.

Before firing, the system (gun and the bullet) is at rest. So, the momentum before firing is zero.

After firing, the bullet leaves the gun and moves in the forward direction with a large velocity.

Since, no external force acts on the system, so its momentum after firing must also be zero.

This can only happen if the gun has a momentum equal to that of the bullet in the backward direction. Thus, to conserve momentum, the gun recoils or moves backward.