When a currentof 2Aflows in a batteryfromnegative to positive terminal, thepotential difference acrossit is 12V. If a current of 3Aflowing in the opposite direction produces a potential difference of 15V, theEMF of the battery is(A) 12.6 V (B) 13.2 V (C) 13.5 V (D) 14.0 V

                                                                     
                                                                     
                                                                     
                                             
Dear   LILAMAYA MISHRA,

As the voltage developed across the battery depends upon the direction of current there will be an internal resistance in the battery which probably you might be missing. take that to be r ,  let the EMF of the battery to be E ,
writing equations ,
- to +  flow of current  INSIDE THE BATTERY -----   E - 2 *r =12
+to -  flow of current ------    E + 3 * r =15
 solve the equations ---
E =13.2 V
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