# Simple momentum question

• sameeralord

#### sameeralord

In this collision

Before= p=100 kg m/s---> <-----p=120 kg m/s
After= <--combined unit P= 20 kg m/s

In this question when I work out the change in momentum for 2 objects it is not the same. When there is a combined unit traveling after the collision can't you find the change in momentum?

What's the problem? The total momentum is 20 kg-m/s to the left both before and after the collision.

phyzguy said:
What's the problem? The total momentum is 20 kg-m/s to the left both before and after the collision.

How do you find the change in momentum of each object? Is the data insufficient?

I see your question. Unless you know the masses of the two objects, you don't know how much of the final momentum belongs to each object, so you can't calculate the individual changes.

## 1. What is momentum?

Momentum is a scientific concept that describes the quantity of motion an object has. It is determined by an object's mass and velocity, and is a vector quantity, meaning it has both magnitude and direction.

## 2. How is momentum calculated?

Momentum is calculated by multiplying an object's mass by its velocity. The formula for momentum is p = m * v, where p is momentum, m is mass, and v is velocity. The standard unit of momentum is kilogram meters per second (kg*m/s).

## 3. What is the law of conservation of momentum?

The law of conservation of momentum states that in a closed system, the total momentum remains constant. This means that the total momentum before a collision or interaction is equal to the total momentum after the collision or interaction. This law is based on the principle of inertia and is a fundamental principle in physics.

## 4. How does momentum relate to Newton's laws of motion?

Momentum is closely related to Newton's laws of motion. The first law of motion states that an object will remain at rest or in motion at a constant velocity unless acted upon by an external force. The second law of motion states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass. The third law of motion states that for every action, there is an equal and opposite reaction. Momentum helps to quantify these laws and understand the effects of forces and motion on objects.

## 5. How is momentum used in real life?

Momentum has many practical applications in real life. It is used in sports, such as calculating the momentum of a ball in motion, and in transportation, such as the momentum required to launch a rocket into space. Momentum is also important in car safety, as it helps determine the force of impact during a collision. Additionally, understanding momentum is crucial in engineering and design, as it helps predict the movement and stability of structures and machines.