A momentum analysis lab trying to get a better understanding

[pongobear]

1. Dropped a .057kg tennis ball and .0027 kg pingpong ball (the pingpong ball is resting directing on top of the tennis ball) from .5 m. Measure the height of the pingpong ball's rebound.

PPm = .0027 kg
TBm = .057 kg

PPwidth = .04 m
TBwidth .065 m

Drop Height:

PP = .565 m
TB = .5 m

Post Collision Height:

PP = 1.3 m
TB = approx. .12 m*

* We observed the height of the to be approx. .12 m., but this is where my confusion starts. I am not sure if the collision occurred at .12 m because the balls drop at different speeds.(and the TB hits the ground first, then collides with the PP at .12 m) OR if the balls drop together and hit the ground as one unit, with the PP taking most of the KE upward to the 1.3 m, and the TB only rebounding .12 m after transferring its energy.





2. V2 = Vo2 + 2a(d)



3. So how would you look at this experiment and where would you note the transfers of energy.

At this point I am looking at as the TB dropping at a certain velocity, with the PP directly above it falling at another velocity. (During the fall a small displacement occurs between the two balls) The TB collides with the earth, and rebounds in the opposite direction with essentially the same momentum. (The transfer of energy between the TB and Earth is infinitesimally small) The falling PP collides with the TB at the .12 m. This is a second collision. The one that I want to analyze.

So with P = mv and KE = 1/2mv^2, and the assumption that P1 = P2, we have the (Ptb1 + Ppp1) = (Ptb2 + Ppp2) I can figure the momentum of all the objects, but I am still not sure how to view the problem.

I am looking for some ideas of how one would attack this problem. I completed the experiment and handed in my report, but I am trying to gain a better understanding of how to view the event. (my physic's vision (as my prof calls it) is not developing as quickly as I would hope)

 

[AvroArrow]

I am looking to analyze the collision between the two balls with respect to energy transfers. How would you approach this problem and where would you note the transfers of energy?

 

[kerimek]

I would first commend the researcher for conducting a well-designed experiment and collecting accurate data. Momentum analysis is an important tool in understanding the physical behavior of objects in motion.

Based on the data provided, it seems that the collision between the tennis ball and pingpong ball occurred at a height of approximately 0.12 m. This can be further confirmed by analyzing the post-collision heights of the two balls. The pingpong ball reached a height of 1.3 m, which is significantly higher than its initial drop height of 0.565 m. This suggests that it gained additional energy from the collision with the tennis ball.

In terms of energy transfers, it is important to note that energy is always conserved in a closed system. In this experiment, the system includes the tennis ball, pingpong ball, and Earth. During the first collision between the tennis ball and Earth, there is a transfer of kinetic energy from the tennis ball to the Earth, which is why the tennis ball rebounds at a lower height than its initial drop height. However, as the pingpong ball was resting on top of the tennis ball, it also experienced a transfer of energy from the tennis ball during this first collision.

The second collision between the pingpong ball and tennis ball can be analyzed using the principle of conservation of momentum. As you have correctly stated, the total momentum before and after the collision must be equal. This means that the momentum gained by the pingpong ball during the first collision must be transferred to the tennis ball during the second collision. This also explains why the pingpong ball rebounds at a higher height than its initial drop height, as it has gained additional energy from the collision with the tennis ball.

In conclusion, this experiment provides a good understanding of the principles of momentum and energy transfers. To further improve your understanding, you can consider varying the initial drop heights and masses of the balls, and analyzing the effects on the collision and rebound heights. You can also explore the concept of elastic and inelastic collisions, which will affect the amount of energy transferred between the balls during the collision. Keep up the good work in developing your "physics vision" and continue to ask questions and seek understanding.