A periodic voltage waveform observed on an oscilloscope across a load is shown. A permanent magnet moving coil (PMMC) meter connected across the same load reads.
a) 4V
b) 5V
c) 8V
d) 10 V
Ans. (a)
Explanation –
As PMMC meter reads only DC value or average value.
V_{avg}=\frac{Area\; under\; the \; curve}{Total \; Time} V_{avg}=\frac{\left ( \frac{1}{2}\times 10\times 10 \right )+(-5 \times 2)+(5\times 8)}{20} V_{avg}=\frac{80}{20}=4V