Hi, I would appreciate it if someone would respond to these questions on my science fair project. It would help me out so much on my backround research paper. Thank you
1. Why does different size wheels affect your speed?
2. What type of surface would be best to skateboard on?
3. What makes a really good bearing?
4. Using my skateboard, how could I test which type of surface has the most friction?
thank you,
Dallas rules
questions about science fair project on skateboarding
You can form a hypothesis and test most of your questions. To test the best surface for skateboards, you will need to define what you mean by "best". Does that mean it is fast, or soft when you fall, or does not break when you roll over it.
Wheel size and speed can be tested by pushing a board with different size wheels with the same force , maybe by rolling down a ramp and timing it over a set distance to calculate velocity, or get a timing gate and measure velocity near the bottom of the ramp.
For a really good bearing, you can try different types of bearings on the board and use the ramp method. You can measure velocity and total distance the board will go before stopping. Make ten or more tests with each type of wheel.
One way to test coeeficient of friction is to have an inclined ramp that can be adjusted. You can test this, but not with a skateboard. The genius of wheels is that they turn and actually use friction to their advantage. So a wheel will roll over a rough surface. A perfectly slippery surface will actually cause the wheels to slip and will not propel the skateboard. ( Think of a skateboard on wet ice, the wheels would not turn.)
You can check friction of surfaces relative to each other in many ways. Make a ramp out of the surface you want to test such as smooth concrete, rough concrete, or asphalt. You can use a block of wood, or a piece of plastic as a sled. If the ramp is fixed in place, more weight is added to the sled until it finally slides down the ramp. If you can raise the angle of the ramp do that until the sled slides. Note the angle. Repeat many times and use the mean. Then do the same for a ramp made of the next material and the next. You will detemrine which has the most friction.
Wheel size and speed can be tested by pushing a board with different size wheels with the same force , maybe by rolling down a ramp and timing it over a set distance to calculate velocity, or get a timing gate and measure velocity near the bottom of the ramp.
For a really good bearing, you can try different types of bearings on the board and use the ramp method. You can measure velocity and total distance the board will go before stopping. Make ten or more tests with each type of wheel.
One way to test coeeficient of friction is to have an inclined ramp that can be adjusted. You can test this, but not with a skateboard. The genius of wheels is that they turn and actually use friction to their advantage. So a wheel will roll over a rough surface. A perfectly slippery surface will actually cause the wheels to slip and will not propel the skateboard. ( Think of a skateboard on wet ice, the wheels would not turn.)
You can check friction of surfaces relative to each other in many ways. Make a ramp out of the surface you want to test such as smooth concrete, rough concrete, or asphalt. You can use a block of wood, or a piece of plastic as a sled. If the ramp is fixed in place, more weight is added to the sled until it finally slides down the ramp. If you can raise the angle of the ramp do that until the sled slides. Note the angle. Repeat many times and use the mean. Then do the same for a ramp made of the next material and the next. You will detemrine which has the most friction.
Kraig Kurucz