Question

In an A.C source, peak value of A.C is the maximum value of current in either direction of the cycle. Root mean square (RMS) is also defined as the direct current which produces the same heating effect in a resistor as the actual A.C.

A.C measuring instrument measures its

• A. rms values
• B. peak value
• C. average value
• D. square of current

Answer 1

The correct option is A rms values

since the actual value of A.C. is not constant and changes too frequently to measure every time but since the change is only in sign a meter measuring value irrespective of sign would work therefore hot wire ammeters work perfectly they measure Root mean square values ,as heat is function of squares of $I,V$ and sign doesn't matter.