Home
Class 12
PHYSICS
A voltmeter with resistance 2500 Omega i...

A voltmeter with resistance `2500 Omega` indicates a voltage of `125 V` in the circuit shown in figure. What is the series resistance to be connected ot voltmeter so that it indicates `100 V`? Consider ideal battery.

A

`625 Omega`

B

`120 Omega`

C

`550 Omega`

D

Data insufficient

Text Solution

Verified by Experts

The correct Answer is:
A
a. `R_0= 2500 Omega`
`E = 125 V`
When r is connected in series,
`i = E/(R_0 +r)`
Reading in voltmeter = `E - ir = 100`
`100 = 125 - (125)/(2500 +r) xx r`
or `r = 625 Omega`.
Promotional Banner

Similar Questions

Explore conceptually related problems

In the circuit shown in figure the resistance of voltmeter is 6kOmega . The voltmeter reading will be

A voltmeter of resistance 1000 Omega is connected across a resistance of 500 Omega in the given circuit. What will be the reading of voltmeter

In the circuit figure, the voltmeter reads 30 V. The resistance of the voltmeter is

A voltmeter of resistances 400(Omega) is used to measure the potential difference across the 100(Omega) resistor in the circuit shown in figure.(a) What will be the reading of the voltmeter ?(b) What was the potential difference across 100(Omega) before the voltmeter was connected ?

The voltmeter shown in figure reads 18V across the 50(Omega) resistor. Find the resistance of the voltmeter.

A 100 V voltmeter having an internal resistance of 20 k Omega is connected in series with a large resistance R across a 110 V line. What is the magnitude of resistance R if the voltmeter reads 5 V ?

To convert a voltmeter measuring 15 V into a voltmeter measuring 150V, if the resistance of the voltmeter is 1000 Omega , the resistance to be connected is