Exploring Momentum & Kinetic Energy w/ an Air Track

[physicsguru97]

Homework Statement

Hello I've been doing this experiment which is about momentum and kinetic energy. I'm using an air track and using two carts one 3/4 of the way down with 50g weights I will add to it each time I test it this will be the variable i will be changing the cart will stay stationary. I will launch another cart with a constant velocity each time and it will hit the cart. My hypothesis is that when you increase the weight of the stationary object the distance of the cart moving will be further than the stationary cart. I also have to use all laws i could get out of this experiment

Homework Equations

i think i can talk about the conservation of momentum and energy i am really unsure what else i can talk about and i have to show working out using formulas

The Attempt at a Solution

I believe i can calculate the acceleration using a stop watch but could anyone else suggest any more equations and how to work it out I am quite unsure

 

[vk6kro]

Air tracks sometimes have a spark system so they leave marks on a paper tape every 1/25th of a second.

If yours has provision for this, you can do accurate tests.

Others have "ticker timers" which drag a paper strip through a stamping device which also leaves a mark. These are not as good as spark timers, but better than stop watches.

So it would be worth checking if any better timing is available.

 

[NascentOxygen]

My hypothesis is that when you increase the weight of the stationary object the distance of the cart moving will be further than the stationary cart.

I'm not sure about "distance" when the carts are moving on a low friction level track.

If you have editing software you maybe could use the frame rate of your webcam to determine the speeds of the carts. Regular cm marks are visible on the tracks?

 

[vk6kro]

If the two carts have equal mass, the stationary cart will move away from the point of contact, while the moving cart will stop.

If the moving cart is lighter than the other, it will reverse direction and go back the way it came, but slower. The stationary cart will move in the opposite direction.

You can probably guess what will happen if the moving cart is the more massive.

 

[Nickie]

I would say that your experiment is a great way to explore the concepts of momentum and kinetic energy. By using an air track and varying the weight of the stationary cart, you are able to investigate how these variables affect the distance the moving cart travels after impact.

Your hypothesis is also very logical. According to the law of conservation of momentum, the total momentum of the system (the two carts) should remain constant before and after the collision. This means that as the weight of the stationary cart increases, the momentum of the system also increases, resulting in a greater distance traveled by the moving cart.

To calculate the acceleration, you can use the formula a = Δv/Δt, where a is the acceleration, Δv is the change in velocity, and Δt is the change in time. You can measure the change in velocity by timing how long it takes for the moving cart to travel a certain distance before and after the collision.

In addition to the law of conservation of momentum, you can also use the law of conservation of energy to analyze your results. The total kinetic energy of the system should also remain constant before and after the collision. By calculating the kinetic energy of each cart before and after the collision, you can determine if the results support the law of conservation of energy.

Overall, your experiment is a great way to explore these important concepts in physics. I would also suggest considering other factors that may affect the results, such as friction and air resistance, and finding ways to control for them in your experiment. Good luck!