Figure 3.33 shows apotentiometer with a cell of 2.0 V and internal resistance 0.40Ω maintaininga potential drop across the resistor wire AB. A standard cell whichmaintains a constant emf of 1.02 V (for very moderate currents up toa few mA) gives a balance point at 67.3 cm length of the wire. Toensure very low currents drawn from the standard cell, a very highresistance of 600 kΩ isput in series with it, which is shorted close to the balance point.The standard cell is then replaced by a cell of unknown emf ε andthe balance point found similarly, turns out to be at 82.3 cm lengthof the wire.(a) What is thevalue ε ?(b) Whatpurpose does the high resistance of 600 kΩ have?(c) Is thebalance point affected by this high resistance?(d) Is thebalance point affected by the internal resistance of the driver cell?(e) Would the method work in the above situation if thedriver cell of the potentiometer had an emf of 1.0 V instead of 2.0V?(f ) Would the circuit work well for determining an extremelysmall emf, say of the order of a few mV (such as the typical emf of athermo-couple)? If not, how will you modify the circuit?