How Do Gliders Behave in an Elastic Collision?

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In an elastic collision between two gliders, kinetic energy and momentum are conserved. The first glider has a mass of 0.156 kg and moves at 0.9 m/s, while the second glider has a mass of 0.293 kg and moves at 2.25 m/s in the opposite direction. To solve for their final velocities after the collision, one can use the conservation of momentum equation and the conservation of kinetic energy equation. By substituting the known values into these equations, the final velocities can be determined. Understanding these principles is crucial for accurately solving the problem.
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A glider of mass 0.156kg is moving to the right on a frictionless, horizontal air track with a speed of 0.9m/s . It has a head-on collision with a glider 0.293kg that is moving to the left with a speed of 2.25m/s . Suppose the collision is elastic.

We've haven't covered elastic collisions in lecture so I have clue how to do this. Any tips or suggestions are VERY welcome.. Thanks
 
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Elastic collision have the unique situation that energy is conserved. So the way to attack this problem is to use the conservation of energy along with the conservation of linear momentum. I am assuming that you are to find the final velocities of the two gliders after the collision? So you will have 2 equations(conservation of energy and momentum) with 2 unknowns (the final speeds of the 2 gliders), and therefore the problem is able to be solved using this method.
 


Sure, I'd be happy to provide some tips and suggestions on how to approach this problem.

First, it's important to understand what an elastic collision is. An elastic collision is a collision between two objects where the total kinetic energy is conserved. This means that the total kinetic energy before the collision is equal to the total kinetic energy after the collision. In other words, the objects bounce off each other without any loss of energy.

Now, let's break down the problem. We have two gliders, one with a mass of 0.156kg and a speed of 0.9m/s moving to the right, and the other with a mass of 0.293kg and a speed of 2.25m/s moving to the left. They collide head-on, meaning they are moving in opposite directions and will collide directly in the middle.

To solve this problem, we can use the conservation of momentum and the conservation of kinetic energy equations.

Conservation of momentum:
m1v1 + m2v2 = m1v1' + m2v2'
Where m1 and m2 are the masses of the two gliders, v1 and v2 are their initial velocities, and v1' and v2' are their final velocities after the collision.

Conservation of kinetic energy:
1/2m1v1^2 + 1/2m2v2^2 = 1/2m1v1'^2 + 1/2m2v2'^2
Where m1 and m2 are the masses of the two gliders, v1 and v2 are their initial velocities, and v1' and v2' are their final velocities after the collision.

We know that the collision is elastic, so we can set the initial and final kinetic energies equal to each other. We also know that the gliders collide head-on, so their initial velocities are in opposite directions and their final velocities will be in opposite directions as well.

Now, we can plug in the values given in the problem into the equations and solve for the final velocities. Once we have the final velocities, we can use them to calculate the kinetic energy of each glider after the collision to make sure that the total kinetic energy is conserved.

I hope this helps and gives you a good starting point for solving the problem. Remember to always start by understanding the concept and then breaking down
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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