Question

A current in circuit is given by i = 3 + 4 sinwt then the effective value of current is

Answer 1

If an instantaneous current is $\bold{I=I_{dc}+I_{ac}}$
= a + bsinωt , where Idc denotes direct current and Iac denotes alternating current.
Then, effective current is given by $\bold{I_{eff}=\sqrt{a^2+\frac{b^2}{2}}}$

Given, I = 3 + 4sinωt
Compare from above equation
a = 3 and b = 4
Now, Ieff = $\bold{I_{eff}=\sqrt{3^2+\frac{4^2}{2}}} =\sqrt{17}A$

Hence, answer is √17 A

Answer 2

Answer:

we know that :-   I=A+Bsinwt   than:-- I=√A²+B²/2

Explanation:  so i=3+4sinwt Ans=√ 3²+4²/2=√9+8=√17A