First and foremost, I wish we kept our designs simple from the beginning instead of trying more complex and complicated designs. Large wheels have greater rotational inertia than small wheels. Rotational velocity is the amount of rotations per second. Newton's first law applies to the performance of our vehicle in that we must remember that the car has inertia, thus will tend to stay at rest when at rest or stay in motion when in motion. Above all, your car should be light. Based on the mass of the car and gravity, you can find the vertical force. If the floor has much better grip, it might work ok without them.
In practice, this means that once they start rolling, they're harder to stop rolling. Make sure that the axles are straight and that there is room for them to spin in the eye hooks. Hub — this the center of the wheel which attaches to the axle. Your string is the part that will transfer force from the spring mechanism of your mousetrap to the rear wheels of your car. This equation gives the torque applied to the pivot point, this is the mechanical advantage concept. The amount of surface friction acting between two object depends on the kinds of material from which the two surfaces are made and how hard the two surfaces are pressed together. Some method of adjusting the steering and then setting it may be desirable.
This will add extra energy to the mousetrap car and it will travel farther as a result. If what you're doing allows you, you can add rubber bands to the front and ack wheels, and see if it goes farther. Through workshops I have taught a fairly large number of mousetrap cars of my design have been built. On the other hand, a shorter lever is better for speed cars because it will provide more force and power. The device must come to a rest as close as possible to a point directly inline from its start location i. The gearing of the mousetrap car can affect its travel distance and acceleration. A single front wheel was used throughout the experiment Tests were ran to determine how far the car would travel and how fast they traveled a distance of five and feet.
It is not meaningful to add or subtract horizontal and vertical forces like you do there. What are the two types of friction present? If there were no friction it would continue to move in the same direction but the friction is an unbalanced force can you think of sources friction in the mousetrap car? No need to introduce so many different notations and different forces. Think of the rear wheel of a bicycle; a small drive gear and a large wheel. For the lever arm it needs to be shorter than compared to the distance car because the shorter the arm is the quicker the spring will snap and the more torque you will get from the spring. The question is, does 7. This may help you to get the right size the first time.
The spring should be found in the middle of the trap and snapper arm. As observations contradict this thought experiment, the assumed lack of friction cannot exist. By winding the spring on your mousetrap car, you store energy in the spring as potential energy. You're going to need to attach your mousetrap to a chassis or body , which will form the frame of your car, wheels, and an engine to power the contraption. Based on the mass of the car and gravity, you can find the vertical force.
Those more ambitious might want to brace it with something between the spring and the back to make sure it doesn't snag or fray, but I didn't bother, which does mean the string gets tangled or frays every so often. Try using graphite powder or even replacing bushings with ball bearings. During the construction of your car, you will have to make some compromises between performance and efficiency. Use a narrow rear axle. A small diameter of the axle in comparison to the wheel will require more force to get started but will cover more ground per rotation.
Every time your axle turns one time, so do your wheels — if the wheels have a much larger diameter than the axle, the car will go further on each turn of the axle than it would if the wheels were smaller. The lever is attached to a string that is wound around the back axle of the car. Remember that, depending on the goal of the car, you may want the car to have some inertia so it will keep moving after the mouse trap has used all it energy. Rotational velocity actually was a problem with our mousetrap since the front wheels were moving having to rotate faster to keep up with our back wheels which had a greater tangential speed. The cause of surface friction is mutual contact of microscopic irregularities that exists on all surfaces. The delicate balance between achieving the maximum distance and making your car unstable can be quite tricky to get right, but don't be afraid to experiment.
You have to determine the ideal drive wheel diameter with trial and error. Upon release, as the trap moves back to resting position, the string rotates the axle which powers the car. A heavy mousetrap will need more force to cause motion that a light mousetrap to achieve equal acceleration. Try not to have any extra frame material beyond what's necessary to keep your mousetrap and wheel axles in place. Large Wheels — using really large diameter drive wheels gives even larger mechanical advantage for greater distance. If all wheels are slipping, the ratio gives you the coefficient of dynamic friction. That way the car will not have much drag in the front, slowing it down.
Relate This to Real World Example Check out my blog post: Terminology Acceleration — most of the mousetrap car lab exercises I have seen deal with total distance and measuring acceleration. I'm sure something else would work washer, appropriately sized nut, etc , tabs from soda cans was the available shapeable piece of metal I grabbed at the time. So when you pull the snapper arm across the mousetrap, it hits it. With the metal rod you attach to the mousetrap, you can add either another hole, or a little slit in the rod. Gather your mousetrap car making materials. Bracing was added to stiffen the chassis which solved the problem. If you were running, you could go pretty fast by yourself.