Justin Geeslin
Eng Physics I - M 1:00
Experiment Eight – Energy of a Tossed Ball
Introduction
This experiment demonstrates, once again, the effects of gravity however, this time we can see its effect on the energy of an object. This experiment involves tossing a ball upward and then letting the ball return to it’s point of origin by gravity. The acceleration due to energy and the deceleration due to gravity are clearly expressed.
Procedure
The setup includes basketball for the projectile. The energy will be measured by a motion detector under the ball’s path. The detector should be protected in the event the ball should strike the detector. The ball should be allowed to rise and fall directly above the motion detector. This will send data to the computer to be used to create a graph. First the mass of the ball must be recorded. Then, hold the ball about 0.5m above the motion detector. When the detector begins it’s data collection, gently toss the ball upward so that it travels straight upward and straight back downward. The ball should be caught at the same point it was released for a more accurate reading. The ball should reach a height of about 1.5m. Once a good reading is obtained, at three points in the ball’s path, the time, height, and velocity must be recorded. From this information one can compute the potential and kinetic energies of the ball with the following equations
Potential Energy = mgh
Kinetic Energy = (1/2)mv2
Total Energy = Potential + Kinetic
Data should be as follows:
|
Mass of the Ball |
0.6075 kg |
|
Position |
Time |
Height |
Velocity |
PE |
KE |
TE |
|
After Release |
0.8658 |
0.684 |
3.75 |
4.07 |
4.27 |
8.34 |
|
Top of Path |
1.3 |
1.426 |
0 |
8.49 |
0 |
8.49 |
|
Before Catch |
1.6 |
0.888 |
-3.02 |
5.29 |
2.77 |
8.06 |
Questions
The energies of the ball remain about constant. This is accounted for by the nature of projectile motion. The amount of force that is required to move the ball, in order for the ball to return to its origin, the same amount of energy must be used to counter it. Therefore, the ball’s total energy should be constant.
When using a beach ball, if the force remained constant the height would be much greater because the mass is much less. The energies should be about the same if the force is constant.
The energies would not be correct if the mass was measured incorrectly.