In the PMMC type instrument, the deflection is directly proportional to the current flowing through the instrument, we get a uniform scale for the instrument. It gives a uniform scale of upto 270° or more. Td ∝ I
The size of the conduit is 62 meters. In conduit, there is a 2-phase wire and 1 neutral wire. Therefore the total number of conducting wire is 3 in a conduit Total length of cable = 62 × 3 = 186 meters.
The resistivity of iron at 20°C is 9.71 × 108 The resistivity of silver at 20°C is 1.59 × 108 The resistivity of Glass at 20°C is 1.10 × 109 The resistivity of nichrome at 20°C is 100 × 108 Hence silver is the least resistive material in the given option.