Chapter 3 Current Electricity
- 12 cells, each having the same emf are connected in series and are kept in a closed box. A reverse cell decreases the emf by 2 ε. Let ‘n’ cells be in opposition, then in the first connection 12ε – 2nε + 2ε = 3R 14ε – 2 nε = 3R …... 1
- One section AB of a circuit absorbs 53.0 W of power when a current i = 1.20 A passes through it in the direction shown. Let ‘r’ be the internal resistance of C. The power relation is i²(R + r) = 53.0 But R = 19.0 and i = 1.20 A r = frac53.0(1.2)² – 19.0 = 17.8... 1