Home
Class 12
PHYSICS
A potentiometer wire of length 10 m and ...

A potentiometer wire of length 10 m and resistance `20Omega` is connected in series with 15V battery and external resistance `40Omega`. A secondary cell of emf E is balanced by 240 cm long potentiomteter wire. The emf of the cell is

A

2.4 V

B

1.2 V

C

2 V

D

3 V

Text Solution

Verified by Experts

The correct Answer is:
B
Promotional Banner

Similar Questions

Explore conceptually related problems

A potentiometer wire of length L and a resistance r are connected in series with a battery of emf E_(0) and resistance 'r_(1)' . An unknown emf E is balanced at a length 'l' of the potentiometer wire. The emf E will be given by

A potentiometer wire of length 100 cm has resis tance of 10 ohms. It is connected in series with a resistance R and a cell of emf 2V and negligible in ternal resistance. The circuit is as shown below. -If a source of emf 10 milli volts is balanced by a length of 40cm of the potentiometer wire, find the value of the external resisatnce

A potentiometer wire of length 100 cm has resis tance of 10 ohms. It is connected in series with a resistance R and a cell of emf 2V and negligible in ternal resistance. The circuit is as shown below. - What is the principle of a potentiometer ?

A potentiometer wire of length 100 cm has resis tance of 10 ohms. It is connected in series with a resistance R and a cell of emf 2V and negligible in ternal resistance. The circuit is as shown below. - Why is it prefered over a voltmeter ?