Home
Class 12
PHYSICS
Two cells of emfs 1.5 V and 2.0v hav...

Two cells of emfs 1.5 V and 2.0v having internal resistance 0.2`Sigma` and 0.3 `Sigma` respectively are connected in parallel . Calculate the emf and internal resistance of the equivalent cell .

Text Solution

Verified by Experts

`E_1 = 1.5 V, r2 = 0.2Omega`
`E_2 = 2.0 V, r_2 =0.3Omega`
emf of equivalent cell’
`E=(E_1/r_1+E_2/r_2)/(1/r_1+1/r_2)=(E_1r_2+E_2r_1)/(r_1+r_2)`
`=((1.5xx0.3+2xx0.2)/(0.2+0.3))=(0.45+0.40)/(0.5)V=1.7V`
Internal resistance of equivalent cell
`1/r=1/r_1+1/r_2=(r_1r_2)/(r_1+r_2)`
`=((0.2xx0.3)/(0.2xx0.3))Omega=(0.06)/(0.5)Omega=0.12Omega`
Promotional Banner

Topper's Solved these Questions

  • CBSE EXAMINATION PAPER - 2016

    CBSE COMPLEMENTARY MATERIAL|Exercise SECTION - C|16 Videos
  • CBSE EXAMINATION PAPER - 2016

    CBSE COMPLEMENTARY MATERIAL|Exercise SECTION - E|17 Videos
  • CBSE EXAMINATION PAPER - 2016

    CBSE COMPLEMENTARY MATERIAL|Exercise SECTION - E|17 Videos
  • CBSE BOARD EXAMNATION PAPER (2017 )

    CBSE COMPLEMENTARY MATERIAL|Exercise SECTION E|12 Videos
  • CBSE Examination Paper Delhi–2014

    CBSE COMPLEMENTARY MATERIAL|Exercise SET-III (Questions Uncommon to set-I and II)|9 Videos

Similar Questions

Explore conceptually related problems

The emf of a cell having internal resistance is

If three cell are connected in parallel then equivalent emf……. and equivalent internal resistance is …..

Two batteries of emfs 2 V and 1 V of internal resistances 1Omega and 2Omega respectively are connected in parallel. The effective emf of the combination is

Two cells of e.m.f. 2.5 V and 2.0 V having internal resistance of 1Omega and 2Omega respectively are connected in parallel with similar poles connected together so as to send the current in the same direction through an external resistance of 2Omega . The current in the external resistance is

Three cells of emfs varepsilon_1=1.5 V, varepsilon_2=2.0 v and varepsilon_3 =3.0 V having internal resistances r_1=0.3 Omega r_2=0.4 Omega and r_3 =0.6 Omega respectively are connected in parallel . Find out the equivalent emf and the equivalent resistance of a cell which can replace this combination.

If n cells each of emf E and internal resistance rare connected in parallel, then the total emf and internal resistances will be