Potentiometer measures the potential difference more accurately than a voltmeter, because

A resistance R is connected across a cell of emf epsilon and internal resistance r. A potentiometer now measures the potential difference between the terminals of the cell is V. Write the expression for r in terms of epsilon , V and R .

A high resistance voltmeter measures the potential difference across a battery to be 9-0 V. On connecting a 24 2 resistor across the terminals of the battery, the voltmeter reads 7.2 V. Calculate the internal resistance of the battery.

A voltmeter reads the potential difference across the terminals of an old battery as 1.40 V , while a potentiometer reads its voltage to be 1.55 V . The voltmeter resistance is 280 Omega .

To measure a potential difference across a resistor of resistance RS, a voltmeter of resistance Ry is used. To measure the potential with a minimum accuracy of 95%, then

Assertion : Potentiometer is used only to compare potential differences. Reason: The potentiometer draws current from the voltage source being measured .

Voltmeter V and Ammeter A are used to measure the total potential difference of the circuit and the current through each resistor. Which is the correct circuit ?

Potentiometer is superior to voltmeter because

Why do we prefer a potentiometer to measure emf of a cell rather than a voltmeter ?

Phenol is more acidic than alcohol because :

In the experiment of calibration of a voltmeter, a 1.1 V standard cell gets balanced at 440 cm length of wire. The balancing length corresponding to a potential difference between the ends of a resistance comes out to be 190 cm. A voltmeter shows 0.5 V for this potential difference. The error in the reading of voltmeter will be