The given potentiometer has its wire of resistance . When the sliding contact is in the middle of the potentiometer wire, the potential drop across resistor is:

The given potentiometer has its wire of resistance . When the sliding contact is in the middle of the potentiometer wire, the potential drop across resistor is:


Potential difference across resistor is
That is
Hence, answer is
Asked in: JEE Main 2021 (25 Jul Shift 2)