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The Vibrating Spring - Experiment #02

Many objects in the real world have a frequency at which they vibrate. In modern engineering it is required to take this into consideration when designing them. There are many variables which could affect this frequency, therefore test are required to be conducted to see what these variables are and how they affect the vibrations the object undergoes. A vibration occurs when there is an oscillation about an equilibrium point.
A good example for where oscillations occur is in a car’s suspension. The suspension takes a hit when a car goes over a bump or into a pothole. The springs in the suspension then oscillate and make the car “bounce” up and down. This is when the shock-absorbers kick in and damp the oscillations to make the car level again. The variables that could change the oscillations which the suspension undergoes could be the diameter of the springs or the number of coils. This would have been tested when the suspension was designed to make sure the car is safe and comfortable for the driver. The picture on the right shows a typical suspension that would be installed on a car. The coils can be clearly seen in the picture as well as the shock absorber in the centre which damps the oscillations.

In the experiment which has been conducted here the vibrations of certain springs have been observed to see what variables affect the frequency at which they oscillate. The relationships between these variables and their respective frequencies will be investigated and discussed. In theory the wire diameter, mean diameter, number of coils, the material and the mass attached to the end of the spring should all have an effect on the number of oscillations. In this experiment however all the above were considered except for the material of the springs. This was kept constant as the modulus rigidity is expected to