Question

The length of a spring is and its force constant is k. when a weight W is suspended from it, its length increases by x. If the spring is cut into tow equal parts and put in parallel and the same weight W is suspended from them, then the extension will be

• A.
• B.
• C.
• D.

Answer 1

The correct option is A

When the spring is cut into two equal halves each has a spring constant of 2 k. when they are connected in parallel, the effective spring constant is 4 k.
$\therefore W=kx=4k{x}_1$ of $x_1=\frac{W}{4k}=\frac{kx}{4k}\Rightarrow \frac{x}{4}$