How does spring stiffness affect a car's speed around bends? Suspension systems absorb bumps and keep tires on the ground. Stiffer springs might help on curves but slow you down on straights.
You swap springs of different stiffness into a remote-controlled car. Then you run the car on three courses: a straight track, a clockwise loop, and a counter-clockwise loop. You time each run at both full speed and low speed.
Comparing the times reveals how spring stiffness changes performance on curves versus straight lines.
Hypothesis
The hypothesis is that the firmer the suspension, the faster the car is able to travel around bends.
A suspension system uses springs and shock absorbers to keep tires pressed against the road. Stiffer springs resist body roll in turns, which can help a car hold its line through curves. You can test this by swapping springs of different stiffness into a remote-controlled car and timing runs on straight and curved courses.
A spring with a high spring constant is stiff and pushes back hard when compressed. This matters for car suspension because stiffer springs might help on curves but slow you down on straights. You test this by swapping springs of different stiffness into a remote-controlled car and timing runs on different courses.
Method & Materials
You will install springs of different levels of firmness into a remote-controlled car, and then measure the time it takes for the car to complete a straight course, a clockwise course, and a counter-clockwise course.
You will need a Tamiya customized remote-control sports car, springs of different levels of firmness, an electronic metronome, a stopwatch, blank paper and pen, and 40 AAA batteries.
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The results show that the hypothesis should be accepted. Overall, the stiffer the spring, the faster the car travels around bends. However, it is interesting to note that the springs of medium-firmness performed the worst for the round circuit.
Why do this project?
This science project is interesting because it allows students to explore the relationship between the firmness of a car's suspension system and its speed around bends.
Also Consider
Consider experimenting with different types of tires to see if they affect the results, or testing the car's speed on different surfaces.
Full project details
Additional information and source material for this project are available below.
