Planes, Trains, and Automobiles A Poppins Book Nook Science Experiment Topic: Friction My Name Is: --------------------------------------------------------------------------------------------------------- Clip Art by: @Charlotte Braddock 2013
Planes, Trains, and Automobiles Experiment Welcome to a fun experiment for children and students to friction. Purpose The purpose of this experiment is to create a wooden car and then determine how high a ramp must be lifted to make the car overcome the friction of its wheels and start moving down the ramp. Materials Needed You will need the following materials for this experiment: Long board (I used one that was 48 ) Wood for car body pieces Tape Measure Circular wood for wheels (I used and old closet shelf rod) Thin finishing nails Spray Paint Car decorating supplies Tools (see instructions) Note: As an alternative you can simply use cars that are already made like toddler toys, Match Box Cars, Lego creations, hot wheels, etc. If you elect to use those instead, then you can ignore the car creation instructions. Car Creation Instructions To make your cars you will need to gather your supplies and tools. Here are the car materials that we collected. The children and my husband took a look to see what spare wood we had laying around. They found some 2x2 and some slat board for their car bodies. With the children s help, my husband cut the car bodies to different sizes. Elizabeth chose to make her car 5 inches long, Beck made his 6 inches long, and my husband s car is 7 inches long. They also found an old closet rod in our storage room, which my husband used to cut wheels out of. Friction
My husband likes to use a lot of tools, so here are the ones he used this time. Under my husband s supervision, the children made sure to sand all the rough edges on the wheels and saw cut edges to make then smooth and safe. Then it was time to paint them. We used spray paint. No matter what you use, be sure to make sure the paint dries completely before moving on. Here are our car parts drying: Then it was time to assemble the cars. My husband started by choosing the proper size drill bit to allow the nails to go through the wheels to allow them to spin freely. He then drilled a hole in as close to the center of the circular wheels as possible. Then, the children helped my husband push one nail through each wheel and into the side of their cars, but not all the way. They used the tape measure to make sure the wheels were all put on in as close a place to the same as possible to make sure it could roll easily. I tried to get a picture of the cards in this stage, but Elizabeth was so excited her car was made and dry she raced it off to the decorating station immediately.
Once all the cars were completely decorated they looked like this. With the cars done it was now time to do the science experiment on friction. Scientific Question What is friction? If you did not know, friction is defined as the surface resistance to relative motion, as of a body sliding or rolling (lots of physics and engineering textbooks). But what does this mean? Friction is what keeps things on a slope from moving. Once some portion of the force equals mass times acceleration equation is great enough, motion will happen and friction will be overcome. The tires (or wheels in our case) are the surface to which the body (our cars) we are studying is having force (friction) applied to. To study this, physics uses equation. Physics is complicated, but essentially all experiments in motion deal with this equation: Force = mass x acceleration. So, in our case, we will place our cars on the ramp and then slowly start to lift one end of the board. The mass will be simply stated as the weight of our cars. The acceleration we will start to explore is a constant and is gravity. The force will be the only variable and what we will look at. Since this is simple physics for children, we will determine the height at which the mass and acceleration, combined, are enough to overcome the force of the car at rest to make it start rolling down the ramp. When this happens the force has exceeded the friction of the wheels. Scientific Method Under a parent or teacher s supervision, perform the following steps to test friction: 1. Take the large board and place it flat on the ground with the tape measure next to the end, within easy reach. 2. Place one car on the long board with its back tires on, but lined up with the edge. 3. Slowly and carefully lift the end of the long board. 4. Once the car starts to roll down the long board stop lifting the long board. 5. Measure the vertical distance that was needed to start the car moving down the ramp.
Performing measurements on overcoming friction. Scientific Basis As we learned earlier, the car will start to move as soon as the height is great enough to overcome the mass and gravity of applied to the car at rest. Extension To extend this learning, try the same experiment with different types of vehicles, cars, trucks, hot wheels, etc. and/or different lengths and types of materials of the ramp.
Friction Experiment Title: Materials Used: Question: Hypothesis What I think will happen: Method What I did:
Draw a picture of your experiment in the box below. Results: Was my hypothesis correct? Yes No What I learned: