0

Guest

Courses New

A high resistance voltmeter is connected to a dry cell battery. The voltmeter reads 12v when the circuit is open and when a 24 ohm resistance is connected across the battery terminals the voltmeter reads 7.2 volt. Find internal resistance.

A high resistance voltmeter is connected to a dry cell battery. The voltmeter reads 12v when the circuit is open and when a 24 ohm resistance is connected across the battery terminals  the voltmeter reads 7.2 volt. Find internal resistance.

Grade:10

1 Answers

deepak
84 Points
7 years ago
since the voltmeter reads 12v in a open circuit the EMF(E) of the cell is 12v
but when a resistance(R) =24 ohm is connected then the terminal voltage(Tv) of the cell is measured to be 7.2v
let the internal resistance be r,
then by formula,
r=R(E/Tv)−R  ….….….….if you dont know this formula then check the expression for internal resistance of a cell expression in google
substituting the values ,
r=16 ohm
P.S. are you really 10th cause this is an 12th standard problem
 

Think You Can Provide A Better Answer ?

Other Related Questions on Electric Current

View all Questions »

ASK QUESTION

Get your questions answered by the expert for free

Answer and earn gift vouchers

Win Gift vouchers upto Rs 500/-

View courses by askIITians

Design classes One-on-One in your own way with Top IITians/Medical Professionals

Click Here Know More

Complete Self Study Package designed by Industry Leading Experts

Click Here Know More

Live 1-1 coding classes to unleash the Creator in your Child

Click Here Know More

a Complete All-in-One Study package Fully Loaded inside a Tablet!

Click Here Know More