Question

An electric current has both D.C. and A.C. components. D.C. component of 8 A and A.C. component is given as I = 6 sin`omega`t A. So I_rms value of resultant current is ______.

Options

• 8.05 A

• 9.05 A

• 11.58 A

• 13.58 A

Answer 1

An electric current has both D.C. and A.C. components. D.C. component of 8 A and A.C. component is given as I = 6 sin`omega`t A. So I_rms value of resultant current is 9.05 A. 

Explanation:

l_rms =`sqrt(("I"^2)) = sqrt ((8+ 6sinomegat)`

l_rms =`sqrt ((64+ 96sinomegat + 36sin^2omegat)`

l_rms =`sqrt ((64+ 96(sinomegat) + 36(sin^2omegat)`

Since `(sin^2omegat)` = 0.5 and `(sinomegat)` =0

l_rms =`sqrt (64+0 + 36xx 0.5) = 9.05` A