# 17 Momentum Example: Detailed Insight

The momentum example depicts an object’s quantity that links its mass with velocity. The article discusses with momentum example listed below:

## Pushing Object

Newton’s laws state that an object’s velocity changes when a force acts upon it. When we employ a push force to a stationary object along the floor, it will be in a motion along the direction of push force. The quantity that relates an object’s mass with its velocity is called momentum.

Simply saying, when an object is in motion, it holds momentum. The mass remains identical after push force, but an object’s velocity alters its momentum and provides its acceleration.

## Sports

We hear on television that a player or team gains ‘momentum’ in numerous sports settings. In cricket, if a batsman starts hitting sixes and four on every ball, we would say that they get momentum for his team as they now become difficult to stop or get out.

Likewise, If a golfer begins making some great shots, the commentator says they gain great momentum. That means every object or person with either a large mass or high velocity gains significant momentum, which is hard to stop.

## Throwing Ball

When you throw any kind of ball rapidly at a person, it is difficult for them to catch it. Hence, the accelerated ball may hit them hard. If you throw a ball with a small mass or light ball with the same velocity, it is possible for the person to catch it. Therefore, greater the mass, greater the momentum.

But if we throw a light ball more rapidly at the person than a large ball, it also hits them very hard. That means, when we change either mass or velocity, its momentum quantity also gets change.

## Walking

While walking, we apply a muscular force on the floor with each step, which accelerates our body by changing motion. While discussing our velocity and mass while walking, we combined to say our momentum.

In simple words, the momentum (P) is the product of our mass (m) and our velocity (v). i.e., P = mv. Different forces are introduced on each step while walking, which continuously modifies our velocity and momentum.

## Firing Bullet

The firing bullet from the gun is an a large momentum example, even if the bullet has a small mass. When a bullet is inside the gun before firing, its momentum is zero as it is not in motion. But once it fires from the gun, it moves so rapidly that it is impossible to stop.

The fired bullet gains enormous momentum in the forward direction due to high velocity, penetrating other objects having mass. Like a bullet, the gun’s velocity changes as it moves slightly backward when a bullet is fired. That means it also gains momentum after firing but in a backward direction. Therefore, the total momentum of the gun firing a bullet is zero.

Firing a bullet is an example that displays momentum quantity can render destruction by driving an object to travel faster. The bullet is not dangerous, but traveling bullets at high speed can provoke some damage. An object’s momentum and capability to provoke destruction are raised by causing the object to be either more massive or faster.

So, any object given the exact momentum as a firing bullet can also do equivalent damage.

## Karate

Have you wondered how karate exert can break several bricks with one fist? Why won’t the ordinary human do it? Most people think it is because karate experts strengthen their hand bones by regular practicing or exercising over the years. But in my opinion, they practice to become more agile than an ordinary human.

Notice that they fist the brick so rapidly that they attain sufficient momentum to break bricks like firing a bullet penetrating the other objects. Simply saying, they need to develop sufficient momentum to break several bricks in one fist.

## Heavy Truck

The truck carries many goods with a large mass, gaining a large momentum even with a small velocity. That’s the reason it becomes difficult for a heavy truck to stop unexpectedly. Therefore, it travels at a slower speed to avoid major accidents.

A four-wheeler has a small mass compared with a heavy truck that gains low momentum. Hence, a four-wheeler running at high velocity can stop instantly, corresponding to a heavy truck.

## Falling Rocks

Suppose two rocks A and B have distinct masses of 50kg and 90kg, respectively falling on an inclined hill. Which rock will reach the ground more quickly? Rock B has a bigger mass than rock A. Therefore, the friction provided by the hill surface to rock B is much less than on rock A.

That’s why falling rock B accumulated more momentum than rock A and quickly reached the ground.

## Weightlessness

Any objects, including astronauts, are floating inside the spaceship due to weightlessness. In such condition, the acceleration due to gravity g depends on the big mass of the spaceship and not on small masses of astronauts or other objects. Because of weightlessness, an object can effortlessly be pushed by astronauts inside the spaceship.

But even though objects float inside the spaceship, it isn’t easy to modify their velocity and momentum because of their tiny masses compared to a spaceship.

## Playing Football

Playing any sports involves such momentum transfers. That means any object in a momentum can provide momentum to another object at rest. While playing football, when a player kicks a football, it transfers its momentum to the football at rest. The other player received the momentum when they stopped the football.

The football projectile into the air when it acquires momentum from the player who kicks it. Since a ball is kicked at a certain angle, it curves through the air with a certain velocity. Once the ball spins to travel a certain distance in the air after kicking, the air drag force makes it fall towards the ground.

So whatever the momentum received by another player when they stop the football in the air or the ground it may be distinct or less than the momentum gained by the football when it is kicked.

## Rocket Propulsion

We may have noticed the upward thrust force gives the momentum to the rocket to eject it into space. But there is a gas chamber at the rear of the rock which produces hot gases from the combustion of rocket’s fuel.

Though the hot gas does not have large mass, the ejected rockets gain recoil velocity just like firing a bullet from a gun and it gives a momentum to the rocket in downward direction. Therefore, the total momentum of the rocket and its fuel before ejection zero and after ejection is also zero due to hot gas and such a condition is called ‘conservation of momentum’.

## Ox Cart

Suppose you are standing on a well-lubricated ox-cart. Since you and the cart are stationary, the total momentum of the isolated system, including you and the cart, is zero. As soon as you step forward on the cart, it moves backward.

You acquire momentum in the forward direction when you step forward, whereas the cart receives a similar magnitude of momentum in the backward direction. That means the total momentum before and after stepping is zero as per the conservation of momentum.

## Charged Particles

The charged particles traveling within the atom produce equal and opposite forces. Therefore, the collection of charged particles has momentum equal to the vector sum of the individual particle’s momentum. Even the particle’s momentum changes, it is balanced by the change in equal and opposite momentum of another particle.

That means, even in the absence of a net force, the total momentum of the collection of charged particles never varies as per the law of conservation of momentum.

## Accelerating Car

We learned how an object gets momentum when it is at rest. Next, we discuss how an object’s momentum changes. A simple example is accelerating the running car. Accelerating drives a change in velocity, which changes the already gained momentum when any force is applied.

That means the force that provides momentum to an object at rest; also changes an object’s already gained momentum.

Physics is applied while playing badminton on the court, such as kinematic equation and momentum. The game begins with kinematic equations as there is an initial velocity vo and final velocity v and the ability of the shuttle to travel a specific distance x after acceleration a. It is provided by the kinematics equation v = v0 + at.

But when we strike the shuttle by the racket, we change its already gained momentum. The force that alters the momentum is called ‘impulse’, indicated as ΔP (P-P0).

## Playing Baseball

In an isolated system, the total momentum remains the same as per conservation law, even though some momentum may move from one object to another. But what about a scenario that is not an isolated system? While playing baseball, the ball is squished to a specific degree when a batter hits it.

But after some milliseconds, it again recovers its shape. Baseball’s contradiction and rebound action produce heat energy, which is how its momentum is lost or transmitted elsewhere.

## Figure Skater

It is an example of angular momentum denoted by L, the product of moment of inertia I instead of mass and angular velocity ω. The first skater begins spinning slides by pulling their arms to increase angular velocity by decreasing the moment of inertia or rotational inertia.

But to stop the spinning slides, a skater now extends their arms to increase the moment of inertia by decreasing the angular velocity.