Home
Class 12
PHYSICS
First a set of n equal resistors of R ea...

First a set of n equal resistors of R each are connected in series to a battery of emf E and internal resistance R. A current I is observed to flow. Then the n resistors are connected in parallel to the same battery. It is observed that the current is increased 10 times. What is 'n'?

Text Solution

Verified by Experts

When n resistors of value R are connected in series with cell with emf `epsilon` and internal resistance R then current .
`I = (E)/(R + nR) = (E)/(R (1 + n)) " "` .... (1)
Instead n resistor of R value are connected in parallel then current,
10 I = `(E)/(R + (R)/(n))`
`= (nE)/(R (n + 1)) " " ` ... (2)
`therefore 10 I = n ((E)/(R (n + 1) ) ) `
`therefore 10 I = nI " " therefore n = 10 `
Promotional Banner

Topper's Solved these Questions

  • CURRENT ELECTRICITY

    KUMAR PRAKASHAN|Exercise SECTION C (LONG ANSWER TYPE QUESTIONS )|5 Videos

  • CURRENT ELECTRICITY

    KUMAR PRAKASHAN|Exercise SECTION [D] MULTIPLE CHOICE QUESTIONS (MCQs) (MCQs FROM .DARPAN. BASED ON TEXTBOOK)|118 Videos

  • CURRENT ELECTRICITY

    KUMAR PRAKASHAN|Exercise SECTION C (VERY SHORT ANSWER TYPE QUESTIONS)|10 Videos

  • BOARD'S QUESTION PAPER MARCH-2020

    KUMAR PRAKASHAN|Exercise PART-B SECTION -C|4 Videos

  • DUAL NATURE OF RADIATION AND MATTER

    KUMAR PRAKASHAN|Exercise Section-D (MCQs asked in GUJCET/Board Exam)|1 Videos

Similar Questions

Explore conceptually related problems

A set of 'n' equal resistors, of value 'R' each, are connected in series to a battery of emf 'E' ,and internal resistance 'R'. The current drawn is I. Now, the 'n' resistors arc connected in parallel to the same battery. Then the current drqwn from battery becomes 10 I. The value of 'n' is

Write equation of equivalent resistance of n resistors connected in series.

n resistors each of resistance r are connected to a battery of emf epsilon and internal resistance r. Then the ratio of terminal voltage to emf of battery = ...... .

When two resistors of R value connected in parallel what is equivalent 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. then

A set of n identical resistors, each of resistance R Omega , when connected in series have an effective resistance X Omega and when the resistors are connected in parallel, their effective resistance is Y Omega . Find the relation between R, X and Y.

For three resistors of different value connected in series obtain equation of equivalent resistance. From this write equation of n resistors connected in series.

N batteries each of emf E and internal resistance r are first connected in series and then in parallel to an external resistance R. if current through R is same in both cases then.

An inductance L and a resistance R are connected in series with a battery of emf e. Find the maximum rate at which the energy is stored in the magnetic field.