In the ohmmeter in below Fig.M is a 2.50-mA meter of resistance 65.0 Ω. (A 2.50-mA meter d...

In the ohmmeter in below Fig.M is a 2.50-mA meter of resistance 65.0 Ω. (A 2.50-mA meter deflects full scale when the current through it is 2.50 m A.) The battery B has an emf of 1.52 V and negligible internal resistance. R is chosen so that when the terminals a and b are shorted (Rx = 0), the meter reads full scale. When a and b are open [Rx = ∞], the meter reads zero. (a) What is the resistance of the resistor R? (b) What current indicates a resistance Rx of 200Ω? (c) What values of Rx correspond to meter defections of ¼, ½ and ¾ of full scale if the deflection is proportional to the current through the galvanometer?

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