Collision: Momentum, Kinetic Energy & Potential Energy

[astro2cosmos]

in collision we all talk about only momentum and energy. but which form of energy only kinetic no sign of potential energy.why??
suppose a ball is rolled from top of a inclined surface at height L from ground and hit another ball placed at bottom of inclined surface, there occurs a collision b/w these balls. so how the potential energy is implemented in this event?

 

[Doc Al]

In your example the potential energy has been transformed to kinetic energy before the collision takes place.

 

[Ali Inam]

remember whenever a body starts motion, its potential energy is converted into kinetic energy.
At the point before the collision, the kinetic energy of the body is maximum while the potential energy is said to be zero. So, no potential energy can be implemented.
You can start considering potential energy when the ball starts to come into rest, and its motion is somehow decreased.

 

[freireib]

Ali Inam's response is exactly correct, however, it would probably be helpful for you (astro2cosmos) to work through the derivation including the terms you think are missing and see what happens. This is the only way you'll ever be convinced that they don't matter.

 

[PJC01]

In a collision, we typically focus on the momentum and energy involved. This is because these are the most relevant quantities for understanding the motion and outcome of the collision. However, it is important to note that potential energy is also present in a collision, but it may not be as obvious or directly involved in the calculations.

In the example given, where a ball is rolled from the top of an inclined surface and hits another ball at the bottom, potential energy is present in the system. The ball at the top of the inclined surface has gravitational potential energy due to its position at a height L from the ground. As it rolls down the surface, this potential energy is converted into kinetic energy.

When the ball collides with the other ball at the bottom, there is a transfer of kinetic energy between the two balls. However, the potential energy that was present in the first ball is now in the form of kinetic energy in the second ball. This exchange of energy is what allows the second ball to move and continue the motion of the system.

So while it may seem that only kinetic energy is involved in a collision, potential energy is also present and plays a crucial role in determining the outcome of the collision. It is important for scientists to consider all forms of energy in any given system, including collisions, in order to fully understand and accurately predict the behavior of the system.