Explain the relevant circuit diagram, the principle of measurement of low resistance by kelvin’s double bridge. Prove that the condition of balance is independent of the read resistance. Up to what low value it can be used?

Explain the functional block diagram of CRO with neat diagram.

What is lissajous pattern? Explain how phase & frequency can be measured using this figures.

How that driving torque in a moving iron instrument is given by \(\theta = \frac{1}{2K}i^2\frac{\text{d}L}{\text{d}\theta}\) . Where the symbols have their usual meaning.