Home
Class 12
PHYSICS
Two cells of emf E each and internal res...

Two cells of emf E each and internal resistance `r_(1)` and `r_(2)` are connected in series across a load resistance R. If potential difference across the first cell is zero, then find the relation between `R, r_(1)` and `r_(2)`

Text Solution

Verified by Experts

Current l from positive electrondes of both are equal .
`l = (E_(eq))/(R+r_(eq)) = (2E)/(R+ (r_(1) + r_(2)))`
Potential difference across first cell = `V_(A) - V_(B) = 0`
` rArr E - Ir_(1) = 0`
`rArr E - (2E)/(R + (r_(1) + r_(2))) r_(1) = 0`
`rArr R + r_(1) + r_(2) - 2r_(1) = 0`
` rArr R + r_(2) - r_(1) = 0`
`rArr r_(1) = R + r_(2) rArr R = (r_(1) - r_(2))`
Promotional Banner

Topper's Solved these Questions

  • CURRENT ELECTRICITY

    AAKASH INSTITUTE|Exercise Try Yourself|32 Videos

  • CURRENT ELECTRICITY

    AAKASH INSTITUTE|Exercise ASSIGNMENT(SECTION-A(OBJECTIVE TYPE QUESTIONS))|59 Videos

  • COMMUNICATION SYSTEMS

    AAKASH INSTITUTE|Exercise ASSIGNMENT SECTION D (Assertion-Reason)|10 Videos

  • DUAL NATURE OF RADIATION AND MATTER

    AAKASH INSTITUTE|Exercise ASSIGNMENT (SECTION-D)|10 Videos

Similar Questions

Explore conceptually related problems

A circuit consists of two cells, each of e.m.f. E and internal resistances r_(1) and r_(2) are connected in series through an external resistance X. If the potential difference between the ends of the first cell is zero, the value of X in terms of r_(1) and r_(2) will be

Two cells of emf 3V and 5V and internal resistance r_(1) and r_(2) respectively are in series with an external resistance R. if the p.d. across 1 st cell is zero, then R is

Two sources of emf 6 V and internal resistance 3 Omega and 2 Omega are connected to anexternal resistance R as shown. If potential difference across battery A is zero, then the value of R is

Two cells of the same e.mf. e but different internal resistances r_(1) and r_(2) are connected in series with an external resistance 'R'. The potential drop across the first cell is found to be zero. The external resistance Ris

Tow cells with the same emf E and different internal resistances r_(1) and r_(2) are connected in series to an external resistances R . The value of R so that the potential difference across the first cell be zero is

Two cells each of emf E and internal resistacne r_(1)" and "r_(2) respectively are conneted in series with an external resistance R. The potential defference between the terminats of the first cell will be zero when R equal to

[" 27.Two cells of same emf "E" but of different internal resistance "r_(1)&r_(2)" are connected "],[" in series with an external resistance "R" .The potential drop across the first cell is "],[" found to be zero.The external resistance "R" is "]

A cell of emf E has an internal resistance r and is connected to rheostat. When resistance R of rheostat is changed, correct graph of potentail difference across it is