question_answer

An alternating current is given by the equation \[i={{i}_{1}}\cos \omega \,t+{{i}_{2}}\sin \omega \,t\]. The r.m.s. current is given by [MP PMT 1994]

A)            \[\frac{1}{\sqrt{2}}({{i}_{1}}+{{i}_{2}})\]                      

B)            \[\frac{1}{\sqrt{2}}{{({{i}_{i}}+{{i}_{2}})}^{2}}\]

C)            \[\frac{1}{\sqrt{2}}{{(i_{1}^{2}+i_{2}^{2})}^{1/2}}\]

D)            \[\frac{1}{2}{{(i_{1}^{2}+i_{2}^{2})}^{1/2}}\]