(Solved): The natural length of a spring is 20cm and a force of 10N must be exerted hold it stretched to ...

The natural length of a spring is $20\mathrm{cm}$ and a force of $10\mathrm{N}$ must be exerted hold it stretched to a length of $25\mathrm{cm}$. (i) Find, in Newtons, the force $F(x)$ required to stretch the spring from $x$ meters (with respect to its equilibrium position). Be careful with units! $F(x)=$ (ii) Find, in Joules, the amount of work required to stretch the spring from $20\mathrm{cm}$ to $25\mathrm{cm}$. Be careful with units! Answer: Joules FORMATTING: Give the exact value. (iii) Find, in Joules, the amount of work required to stretch the spring from $25\mathrm{cm}$ to $30\mathrm{cm}$. Be careful with units! Answer: Q $\sum$ Joules FORMATTING: Give the exact value.