A) \[\frac{{{k}_{1}}}{2}+{{k}_{2}}\]
B) \[{{\left[ \frac{1}{2{{k}_{1}}}+\frac{1}{{{k}_{2}}} \right]}^{-1}}\]
C) \[\left[ \frac{1}{2{{k}_{1}}}+\frac{1}{{{k}_{2}}} \right]\]
D) \[{{\left[ \frac{2}{{{k}_{1}}}+\frac{1}{{{k}_{2}}} \right]}^{-1}}\]
Correct Answer: B
Solution :
[b] Two springs of force constants \[{{k}_{1}}\] and \[{{k}_{2}}\] are in parallel. Hence \[k'={{k}_{1}}+{{k}_{1}}=2{{k}_{1}}\] The third spring \[{{k}_{2}}\] is in series with spring of force constant k'. \[\therefore \]\[\frac{1}{k}=\left[ \frac{1}{2{{k}_{1}}}+\frac{1}{{{k}_{2}}} \right]\] or \[k={{\left[ \frac{1}{2{{k}_{1}}}+\frac{1}{{{k}_{2}}} \right]}^{-1}}\]
You need to login to perform this action.
You will be redirected in
3 sec
