Question

A bulb draws 2A current from the battery.But when resistance of circuit is raised by 8 ohms,it draw only 1.2 amp current,what is the P.D across terminals of battery(assumed constant)?​

Answer 1

ANSWER

SO IN THE GIVEN Q  I=2A

SO WHEN ITS IN DRAW SO POTENTIAL IN POINT A

V=E-2R

WHEN IT IS RAISED TO 28 THEN RESISTOR WILL BE 8R

SO  V2= E-9.6R

         = 9.6R

THERFORE ,  Vb-Va= 9.6R-2R=7.6R