GoalTo build a mousetrap car that uses the stored elastic potential energy of a mousetrap spring to generate into as much forward motion as possible.
Size of Wheels to Axle ratioIt is very important to have a significant difference between the size of the wheel and the size of the axle. Having a big wheel most of the time does not mean it will travel fast, if the axle is equally as big as the wheel, the speed of mousetrap will just be as bad as one with a small wheel.
Thus, a good design should have a wheel that is bigger in comparison with the axle. The axle should have a small diameter so that a small turn in the axle results in a large turn of the big wheel. This design wheels could lead the car to go further on each turn of the axle.
WeightFrom Newton's second law, force = mass x acceleration. Our objective is to increase the acceleration of the mousetrap. Thus, if we have more mass, the amount of force required to overcome the weight and move the mousetrap is a lot more compared to a lighter mousetrap.
Length of Lever Arm
As we know the more the elastic potential energy stored in the spring, the more kinetic energy it will be converted to. Increasing the length of the lever arm increases the moment, resulting in an increase in elastic potential energy.Having an aerodynamic shape reduces the amount of surface area contact between mousetrap and the particles that make up air. The size of the mousetrap should not exceed 30cm in length, 15cm in width, and 15cm in height.