3 One end of a light elastic spring of natural length 0.3 m is attached to a fixed point. A mass of 4 kg is attached to the other end of the spring.
When the spring hangs vertically in equilibrium the extension of the spring is 0.02 m .
- Determine the modulus of elasticity of the spring.
A student calculates that if the mass of 4 kg is removed and replaced with a mass of 20 kg the extension of the spring will be 0.1 m .
- Suggest a reason why this extension may not be 0.1 m .