Law of conservation of momentum

The essence of all current physics theories is Newton’s equations of motion.This article discusses momentum and how it can be conserved. A moving object’s momentum is defined as the product of its mass and velocity. It is a vector quantity that can be measured in kilogram-metre per second. The direction of a body’s momentum is the same as the direction of the body’s velocity.This is a relative quantity whose value is determined by the frame of reference used.

What is  conservation of momentum?

The conservation of momentum is a fundamental physics principle. Newton’s third law has resulted in this. This universal law of motion states that “the total momentum of any two or more objects in an isolated system acting on each other remains constant until and unless no external force acts on the system,” which means that “the total momentum of any two or more objects in an isolated system acting on each other remains constant until and unless no external force acts on the system.” It is impossible to create or eliminate momentum.

The Logic Behind Momentum Conservation:

Consider the following scenario: two objects, object 1 and object 2, collide. The forces acting on the two objects in such a collision are equal in magnitude and opposite in direction (Newton’s third law). The following equation can be used to express this assertion.

F1=-F2

For a set amount of time, the forces act between the two objects. In some circumstances, the period is extensive, while in others, it is brief. It can be claimed that the time the force acts on item 1 is equal to the time the force acts on object 2 regardless of how lengthy the time is. This is only common sense. Interactions (or contact) between two objects produce forces.If object 1 makes touch with object 2 for 0.050 seconds, object 2 must be making contact with object 1 for the same length of time (0.050 seconds). The equation represents:

t1=t2                      

The impulses experienced by the two objects are equal in magnitude and opposite in direction because the forces between the two items are equal in magnitude and opposite in direction, and the times during which these forces act are equal in magnitude. The equation represents:

F1×t1=-F2×t2

However, an object’s impulse is equal to the change in momentum of that object (the impulse-momentum change theorem). As a result, because each object feels equal and opposing impulses, they must likewise suffer equal and opposite momentum changes. The equation:

m1×v1=-m2×v2

Law of Conservation of momentum uses:

•  Recoiling of a Gun

The abrupt backward movement of a gun after discharging a bullet is known as recoil. Both the rifle and the projectile are at rest before firing, which means the overall momentum is zero. When a bullet is shot, the gun applies force to the bullet, propelling it forward. Bullets, according to the law of conservation of momentum, will exert the same force but in the opposite direction, i.e. backward. Let’s look at it through the lens of the law of conservation of momentum.

A bullet’s mass is m, while the gun’s mass is m2.

In the forward direction, the bullet’s velocity is v.

In the backward direction, the gun’s velocity is v2.

conservation of momentum law:

The total momentum value before firing is zero, and the total momentum value after firing is zero, demonstrating that the law of conservation of momentum is satisfied.

             mv+m2v2 = 0        

              v2 = – (m/m2)v

• Rocket

The fuel in a rocket burns and creates gas at a high temperature. These gases are blasted from the rocket through a nozzle on the rocket’s back side. The rocket accelerates due to the forward force exerted by the ejecting gas. Due to their high velocity of escape, the mass of gases departing per second is relatively little, but their momentum is very large. The rocket receives an equal and opposing momentum, allowing it to achieve a high velocity despite its great mass.

Conclusion:

Along with the conservation of energy and mass, the conservation of momentum is a fundamental idea in physics.. The conservation of momentum states that the amount of momentum remains constant inside a problem domain; momentum is never created nor destroyed, but only altered by the action of forces specified by Newton’s equations of motion. Because momentum is a vector quantity with both a magnitude and a direction, it is more complex to deal with than mass and energy.