question_answer

A spring with spring constant k is extended from \[x=0\]to\[x={{x}_{1}}\]. The work done will be              [Orissa PMT 2004]

A)             \[kx_{1}^{2}\]         

B)             \[\frac{1}{2}kx_{1}^{2}\]  

C)             \[2kx_{1}^{2}\]       

D)             \[2k{{x}_{1}}\]