Hotwheels Friction Sled

thingiverse

This is a sled designed to be placed at the end of a section of hotwheels track. The car rolls into the sled and then slides across the desk/floor. In my classroom I use this as part of our Work and Energy unit. I set up the track like a ramp so the car rolls down and into the sled. Students calculate the gravitational potential energy of the car at the top and measure the distance the sled slides. With this students can use conservation of energy to determine the work done by friction on the sled, then using the distance the sled slid they can find the force of friction on the sled, and even the coefficient of friction. Print Settings Printer Brand: MakerBot Printer: MakerBot Replicator (5th Generation) Rafts: Doesn't Matter Supports: No Resolution: .3 no need for high res Infill: variable. I like 10% Notes: No need to run this on high resolution settings, .3 layer height and low infill is just fine. If you are not having problems with adhesion, no need for a raft, this has a nice wide flat base to stick to the platform. How I Designed This Designing more Autodesk Inventor is a free 3 year license for students or teachers and is great for 3D design. I sized this one to fit the end of the track and cars that we use in our classroom, but feel free to scale or modify to fit your needs. Scaling up and down could also make a great lesson in the impact of surface area on friction (or lack there of) Project: Work done by Friction Physics Lab Objectives Students will be able to determine the relationship between potential energy and work done by friction. Students will be able to apply Newton's Laws and friction equations to the concept of energy conservation to determine the coefficient of friction. Audiences Great for 9-12 physics or physical science students studying work and energy. Could also be used in elementary to develop a more qualitative understanding of why the car will slide further when released from a greater height. Preparation This project also needs hot wheels cars and track or similar. Could be done with rolling a ball or firing a rubber band also. Ideal students would already be familiar with newtons laws, energy transfers and friction. To set up the experiment set a length of track against a wall or propped up on books. Secure the track with tape so it doesn't fall and set the sled at the end of the track. Students will need a measuring device like a meter stick or tape measure. Steps In the thing files you will find the Lab Activity sheet I had out with this lab. Feel free to message me if you would like a word doc version of the sheet so you can modify it. The step by step for the students is all there, you just need to get everything set up and help guide them through! Results By the end of this lab students should have a better grasp on application of work/energy and newtons laws. The connection should be clear. A great extension of this assignment would be to have each group design or modify a new sled to see how it changes the results. I think learning activities like this are important for students to be able to explore. For grading I use a stamping method for completion. Stamp = full credit. We want them to learn and explore, not nitpick points!