# Conservation of momentum query

• cd19
In summary, the total momentum before collision is equal to the total momentum after collision for two objects of mass m1, m2 and velocity u1, u2 traveling along the same path. However, when one object collides at an angle of 30o to the other, the calculation of the resultant velocity should take into account the x and y components of the objects' momentum. This can be done by using the equation (m_1u_1_x + m_2u_2_x)/(m_1 + m_2) = V_x and calculating the resultant velocity in the y direction as well.

## Homework Statement

If two objects of mass m1, m2 and velocity u1, u2 traveling along the same path collide and combine the total momentum before collision is equal to the total momentum after collision. But if one object collides at an angle of say 30o to the other how will this affect your calculation.

## Homework Equations

m1.u1+m2.u2=m1+2.v2

## The Attempt at a Solution

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Hint: Momentum is a vector quantity; as such, it can have x and y components. What are your thoughts on this?

As momentum is a vector quantity, if I get the x and y components of object (a) and object (b) and find the resultant, I guess this will be equal to the total momentum? The question i am attempting wants me to find the velocity of the combined objects after collision, I figure this should be straight forward m1u1+m2u2/m1+2=vtotal but what i am having difficulty comprehending is will the angle of 30o have any affect at all on the final velocity? the answer seems to suggest so, but i can't see how

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Try $$(m_1u_1_x + m_2u_2_x)/(m_1 + m_2) = V_x$$ , and do the same in the y direction to get $$V_y$$, then calculate the resultant velocity.

Thank you, that seemed to work perfectly

## 1. What is the conservation of momentum?

The conservation of momentum is a fundamental law of physics that states that the total momentum of a closed system remains constant over time. This means that the total amount of momentum before a collision or interaction is equal to the total amount of momentum after the collision or interaction.

## 2. Why is the conservation of momentum important?

The conservation of momentum is important because it allows us to predict the outcome of interactions between objects, such as collisions, without having to know all the details of the forces involved. It also helps us understand and describe the motion of objects in the universe.

## 3. How is momentum conserved in a closed system?

In a closed system, momentum is conserved because there are no external forces acting on the system. This means that any changes in the momentum of one object must be counteracted by an equal and opposite change in the momentum of another object in the system, resulting in a constant total momentum.

## 4. What are some real-life examples of the conservation of momentum?

Some real-life examples of the conservation of momentum include a game of pool, where the total momentum of the balls before and after a collision remains the same, and a rocket launching into space, where the momentum of the fuel is transferred to the rocket, propelling it forward.

## 5. How does the conservation of momentum relate to Newton's Third Law of Motion?

The conservation of momentum is closely related to Newton's Third Law of Motion, which states that for every action, there is an equal and opposite reaction. In the case of the conservation of momentum, the action and reaction are the changes in momentum of two objects in a closed system, resulting in a constant total momentum.