Problem: What effect does friction have on the time of a ball rolling down different surfaces?
Hypothesis: I believe that the glass inclined plane will allow the ball to roll down the fastest, because it is the smoothest, so there is less resistance against the ball.
Experiment:
Variables-
IV- friction of the surfaces
CV- same slope, same ball, same person timing
DV- time of ball rolling
Control- wooden inclined plane
Materials-
12 inch long science book
12 inch long covered science book
Stopwatch
Marble
Procedure-
Observations:
***All numbers are represented in seconds***
Conclusion:
When trying to experiment with friction and gravity, I wondered if the speed of a marble would be effected by friction. I believed that the more friction in an object, the slower the marble would go. With the experiment that I did my hypothesis was supported by the facts. The the marble rolling down the uncovered book had an average of .18 seconds, while it took an average of .29 1/3 seconds to roll down the covered book. This is because the covered book was coarser than the uncovered book, which allowed more resistance on the marble when it was rolling down. This resistance is called friction, and the particular friction that is in play here is called kinetic friction. Kinetic friction is created when two objects rub against each other, transfering kinetic energy into heat energy. Most objects on the earth have some degree of friction, but friction can be increased or decreased depending upon the smoothness of the surface. The book cover had a coarser surface than the book, so the there was a higher friction there. Friction restricts the abilities of speed and acceleration, meaning the ball rolls down the covered book slower than down the uncovered book.
Friction and gravity relate directly to many of Newton's Laws. Both can be the opposing force mentioned in the first law that forces the object in motion to stop. Gravity can also be the starting force that allows the object to go from a state of rest into a state of motion. If you were to drop a ball, gravity would be the force to start the motion, but if you throw a ball, gravity is the force that brings the ball to the ground and stops. Friction in the form of grass can cause a soccer ball to stop if you kick it, putting it into motion. The second law of force can be altered due to the aforementioned affects of gravity and friction. Finally, the third law can also be altered or caused in the ways also aforementioned.
Hypothesis: I believe that the glass inclined plane will allow the ball to roll down the fastest, because it is the smoothest, so there is less resistance against the ball.
Experiment:
Variables-
IV- friction of the surfaces
CV- same slope, same ball, same person timing
DV- time of ball rolling
Control- wooden inclined plane
Materials-
12 inch long science book
12 inch long covered science book
Stopwatch
Marble
Procedure-
- Gather all materials
- Take the 12 inch science book and set it up so that one side is on the surface/table and the other is 5 inches above it
- Roll the marble down the inclined plane starting the stopwatch as soon as you do
- Wait for the ball to roll down the length of the book
- When it rolls off, stop the stopwatch
- Record the results
- Repeat steps 3 through 6 twice more with the book inclined plane
- Repeat steps 2 through 6 with the covered book three times
- Clean up station
- Write a conclusion
Observations:
| Trial 1 | Trial 2 | Trial 3 | Average | |
| Covered | 0.26 | 0.23 | 0.39 | 0.293333 |
| Uncovered | 0.17 | 0.19 | 0.18 | 0.18 |
***All numbers are represented in seconds***
Conclusion:
When trying to experiment with friction and gravity, I wondered if the speed of a marble would be effected by friction. I believed that the more friction in an object, the slower the marble would go. With the experiment that I did my hypothesis was supported by the facts. The the marble rolling down the uncovered book had an average of .18 seconds, while it took an average of .29 1/3 seconds to roll down the covered book. This is because the covered book was coarser than the uncovered book, which allowed more resistance on the marble when it was rolling down. This resistance is called friction, and the particular friction that is in play here is called kinetic friction. Kinetic friction is created when two objects rub against each other, transfering kinetic energy into heat energy. Most objects on the earth have some degree of friction, but friction can be increased or decreased depending upon the smoothness of the surface. The book cover had a coarser surface than the book, so the there was a higher friction there. Friction restricts the abilities of speed and acceleration, meaning the ball rolls down the covered book slower than down the uncovered book.
Friction and gravity relate directly to many of Newton's Laws. Both can be the opposing force mentioned in the first law that forces the object in motion to stop. Gravity can also be the starting force that allows the object to go from a state of rest into a state of motion. If you were to drop a ball, gravity would be the force to start the motion, but if you throw a ball, gravity is the force that brings the ball to the ground and stops. Friction in the form of grass can cause a soccer ball to stop if you kick it, putting it into motion. The second law of force can be altered due to the aforementioned affects of gravity and friction. Finally, the third law can also be altered or caused in the ways also aforementioned.
