Conservation of Momentum problem-don't understand the solution

In summary, the conversation is about a solved problem involving the conservation of momentum in a collision between two pucks on an air-hockey table. The initial masses and velocities of the pucks are given, and the final speeds of both pucks need to be found. The solution involves using equations for the x and y directions and plugging in the given information. However, since the drawing and equation (2) are not provided, it is difficult to fully solve the problem.
  • #1
skier07
8
0
[SOLVED] Conservation of Momentum problem-don't understand the solution

Homework Statement



The drawing shows a collision between two pucks on an air-hockey table. Puck A has a mass of 0.025kg and is moving along the x-axis with a velocity of 5.5m/s. It makes a collision with puck B, which has a mass of 0.050kg and is initially at rest. The collision is not head-on. After the collision, the two pucks fly apart with the angles shown in the drawing. Find the final speed of (a) puck A and (b) puck B.

Homework Equations






The Attempt at a Solution


X direction:


Y direction:






Plug into (2)
 
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  • #2
More Information?

skier07 said:

Homework Statement



After the collision, the two pucks fly apart with the angles shown in the drawing.

...

Plug into (2)

No one has posted yet to help you but I think that you should include the drawing and demonstrate what equation (2) is exactly. The lack of information makes your problem difficult to solve...
 
  • #3
to get V2f = 3.7m/s, which is the final speed of puck A. For puck B, we can use conservation of momentum to solve for its final velocity in the x-direction:


V2f = 2.4m/s

The solution provided is correct. It seems that you have correctly applied the conservation of momentum principle to solve for the final velocity of puck A. To solve for the final velocity of puck B, you can use the equation V2f = (m1 * V1i + m2 * V2i)/(m1 + m2), where m1 and m2 are the masses of the two pucks and V1i and V2i are their initial velocities. This equation takes into account the conservation of momentum in both the x and y directions. Plugging in the values given in the problem, we get V2f = (0.025kg * 5.5m/s * cos(45°) + 0.050kg * 0m/s * cos(0°))/(0.025kg + 0.050kg) = 2.4m/s. This is the final velocity of puck B in the x-direction. In the y-direction, the final velocity can be found using the equation V2f = (m1 * V1i + m2 * V2i)/(m1 + m2) * sin(θ), where θ is the angle shown in the drawing. Plugging in the values, we get V2f = (0.025kg * 5.5m/s * sin(45°) + 0.050kg * 0m/s * sin(0°))/(0.025kg + 0.050kg) = 1.85m/s. Therefore, the final velocity of puck B is 2.4m/s in the x-direction and 1.85m/s in the y-direction. I hope this helps clarify the solution for you.
 

1. What is the Conservation of Momentum?

The Conservation of Momentum is a fundamental law in physics that states that the total momentum of a closed system remains constant over time. This means that in any interaction between objects, the total momentum before the interaction is equal to the total momentum after the interaction.

2. How is the Conservation of Momentum applied to problem-solving?

In problem-solving, the Conservation of Momentum is applied by setting the initial momentum of the system equal to the final momentum of the system. This equation can then be used to solve for unknown quantities, such as the velocity or mass of an object.

3. What are some common types of Conservation of Momentum problems?

Examples of common Conservation of Momentum problems include collisions between objects, explosions, and rocket launching. These problems can involve one or more objects and may require the use of different equations and principles to solve.

4. Why is it important to understand the solution to Conservation of Momentum problems?

Understanding the solution to Conservation of Momentum problems is important because it allows us to predict and explain the motion of objects in various scenarios. This knowledge is essential in fields such as engineering, mechanics, and astrophysics.

5. What are some common misconceptions about the Conservation of Momentum?

Some common misconceptions about the Conservation of Momentum include the belief that momentum is always conserved in all situations, when in reality it is only conserved in closed systems. Another misconception is the idea that the mass of an object affects its momentum, when in fact it is the velocity of the object that determines its momentum.

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