How Can I Make a Rubber Ball Bounce in an Excel Simulation?

[Boyd]

Homework Statement

My goal is to create a graph in excel that moves as I hold the F9 key(and progressing the time). The concept is of a 'rubber ball' bouncing after it is dropped from an initial height. The variables that must be left in separate cells (to easily change) are kinetic energy lost on each bounce (max 100%, min 0%), acceleration of gravity, and initial height. (max 50 meters). The mass of the ball is neither given nor is it specified that it is necessary.

Homework Equations

Newton's Second Law
Yf=Yi + (Vi)(delta_t) + .5(g)(delta_t)^2
Momentum Equation?

The Attempt at a Solution

I can get my 'rubber ball' to fall, but I can't figure out what I need to do to make it bounce back up. Any insight would be greatly appreciated.

 

[Boyd]

disregard..nm

disregard..

 

[piercas]

To create a graph in Excel that moves as you hold the F9 key, you can use the "Goal Seek" function under the "Data" tab. This allows you to input a changing value (such as time) and see how it affects the final result (such as the height of the ball). You can also use the "Solver" function to set constraints on the variables that must be left in separate cells, such as the maximum and minimum values for kinetic energy lost and initial height.

To make the ball bounce, you can use the equation for momentum conservation, which states that the initial momentum of the ball (before the bounce) is equal to the final momentum (after the bounce). This can be represented as:

Momentum before bounce = Momentum after bounce

To calculate the momentum before the bounce, you can use the equation:

Momentum = mass x velocity

Since the mass of the ball is not given, you can assume it to be 1 kg for simplicity. The velocity before the bounce can be calculated using the equation:

Velocity = initial velocity + acceleration x time

The initial velocity can be set to 0 since the ball starts from rest. The acceleration can be set to the acceleration of gravity (9.8 m/s^2). The time can be calculated using the "Goal Seek" or "Solver" function mentioned earlier.

Once you have the momentum before the bounce, you can use the same equation to calculate the momentum after the bounce. The only difference is that the velocity after the bounce will be in the opposite direction, since the ball bounces back up.

Once you have the momentum before and after the bounce, you can use the "Goal Seek" or "Solver" function to find the time at which the two values are equal. This will give you the time at which the ball bounces.

You can repeat this process for multiple bounces by using the final height of the previous bounce as the initial height for the next bounce, and adjusting the kinetic energy lost and initial height values accordingly.

I hope this helps. Let me know if you have any further questions. Good luck with your graphing!