Stretching Materials (Edexcel A Level Physics): Exam Questions

When a force F is applied to a spring with stiffness k, the elastic potential energy stored is E.

What is the elastic potential energy stored when a force 2F is applied to a spring with stiffness 2k?

A mass of 24 kg is suspended from a steel wire of length 1.5 m. The wire has cross-sectional area 3.1 × 10⁻⁶ m².

The Young modulus of steel is 1.8 × 10¹¹ Pa.

Which of the following gives the extension of the wire?

A mass is supported by a single spring as shown. 

The strain energy stored by the spring is E.

The mass is then supported by two springs, each identical to the first spring, as shown. 

What is the total strain energy stored with two springs arranged in this way?  

A deforming force is applied to a sample of material.

Which row of the table shows the axes of a graph for which the gradient is stiffness k?

A wire of length $L$ and diameter $d$ extends by $x$ when a force $F$ is applied.

The wire is replaced with a second wire of the same material, of length $3L$ and diameter $\frac{d}{2}$. The same force $F$ is applied to the second wire.

What is the extension of the second wire?