railway RRB JE (CBT I + CBT II) Mock Test 2024 Electrical and Electronics Measurements Measurement of Power
With the usual notations, which of the following equations can measure power factor angle by using the wattmeter method?
1
\(\rm \cos^{-1}\sqrt{1+3\left(\frac{W_1-W_2}{W_1+W_2}\right)}\)
2
\(\rm \tan^{-1}\sqrt3\left(\frac{W_1-W_2}{W_1+W_2}\right)\)
3
\(\rm \cos^{-1}\sqrt3\left(\frac{W_1-W_2}{W_1+W_2}\right)\)
4
\(\rm \tan^{-1}\left(\frac{W_1-W_2}{W_1+W_2}\right)\)