Home
Class 12
PHYSICS
An ammeter and a voltmeter are connected...

An ammeter and a voltmeter are connected in series to a battery with an emf `xi = 6.0 V`. When a certain resistance is connected in parallel with the voltmeter, the readings of the latter decreases `eta = 2.0` times, whereas the readings of the ammeter increase the same number of times, Find the voltmeter readings after the connection of the resistance.

Text Solution

Verified by Experts

Let `R=` resistance of ammeter

Potential difference across voltmeter `=6-` potential difference across ammeter
In first case, `V=6-iR` …………i
In second case, `V/2=6-(2i)R` ……………ii
solving these two equations we get
`V=4`volt
`:. V/2=2` volt
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • CURRENT ELECTRICITY

    DC PANDEY|Exercise Exercise 23.1|6 Videos
  • CURRENT ELECTRICITY

    DC PANDEY|Exercise Exercise 23.2|1 Videos
  • CURRENT ELECTRICITY

    DC PANDEY|Exercise Example Type 6|1 Videos
  • COMMUNICATION SYSTEM

    DC PANDEY|Exercise Subjective|11 Videos
  • ELECTROMAGNETIC INDUCTION

    DC PANDEY|Exercise Medical entrances gallery|25 Videos

Similar Questions

Explore conceptually related problems

An ammeter and a voltmeter are connected in series to a battery with an emf xi = 6.0 V . When a certain resistance is connected in parallel with the voltmeter, the readings of tgeh latter decreases eta = 2.0 times, whereas the readings of the ammeter increase the same number of times, Find teh voltmeter readings after the connection of the resistance.

An ammeter and a voltmeter are connected in series to a battery of emf 6V. When a certain resistance is connected in parallel with the voltmeter, the reading of the latter decreases n = 2 times, whereas the reading of the ammeter increases the same number of times. What is the ratio of the voltmeter resistance to the ammeter resistance? Find the voltmeter reading after the connection.

Knowledge Check

  • An ammeter and a voltmeter are j oined in series to a cell. Their readings are A and V respectively. If a resistance is now joined in parallel with the voltmeter

    A
    both A and V will decrease
    B
    both A and V will increase.
    C
    A will increase V will dec rease.
    D
    A will decrease V will increase.
  • An ammeter, voltmeter and a resistor are connected in series to a cell and the readings are noted as I and V. If another resistor R is connected in parallel with a voltmeter, then

    A
    I and V increase
    B
    I increases
    C
    I and V will remain same
    D
    I decreases
  • An ammeter and a voltmeter are joined in sereis to a cell. Their readings are A and V respectively. If a resistance is now joinding parallel with the voltmeter. Then

    A
    both `A` and `V `will increase
    B
    both and `V` will decreases
    C
    `A` will decrease, `V` will increase
    D
    `A` will increase, `V` will decrease
  • Similar Questions

    Explore conceptually related problems

    (a) A cell of emf 3.4 V and internal resistance 3 Omega is connected to an ammeter having resistance 2 Omega and to an external resistance 100 Omega . When a voltmeter is connected across the 100 Omega resistance the ammeter reading is 0.04 A . Find the voltage read by the voltmeter and its resistance. Had the voltmeter been an ideal one, what would have its reading ? (b) Two resistances of 100 Omega and 200 Omega are connected in series with battery of emf 4 V and negligible internal resistance. A voltmeter of resistance 200 Omega is used to measure voltemeter of resistances separately. Calculate the voltmeter indicated. ( c) In the circuit shown, a voltmeter reads 30 V when it is connected across the 400 Omega resistance. Calculate what the same voltmeter will read when it is connected across the 300 Omega resistance ? (d) An ammeter and a voltmeter are connected in series to a battery of emf E = 6.0 V . When a certain resistance is connected in parallel with the voltmeter. the reading of the ammeter is doubled. while voltmeter reading is reduced to half. Find the voltmeter reading after the connection of the resistance.

    An ammeter of zero resistance and a volt meter are connected in series to a battery of emf 6.0 volt and certain internal resistance. When a resistance R is connected in parallel with the voltmeter the readings of the voltmeter becomes half of its initial reading and the reading of the ammeter becomes 2 times to its initial reading (before R is connected). Find the voltmeter reading in volt after the connection of the resistance.

    A battery of electro motive force E is connected in series with a resistance R and a voltmeter. An ammeter is connected in parallel with the battery.

    An ammeter and a voltmeter are connected in series to an ideal battery of emf E. If the ammeter reads I and voltmeter reading V, then

    Find the readings of the ammeter (A) and voltmeter (V):