(i) The voltmeter should be connected across the points (parallel) where the potential difference is to be measured.
(ii) In series mode
(iii) 4 × 1.5 = 6V
(iv)
If connected in this mode, we get electric current for a long time without variation in voltage.
Combination of cells:
A battery is a combination of two or more cells connected in a suitable manner. Cells can be connected in two ways.
1. Series connection
This is the method of connecting cells one after the other in such a way that the positive of one cell is connected to the negative of another cell.
Salient features:
2. Parallel connection
This is the method of connecting similar potes together.
Salient features:
- If all the cells have equal emf then the emf of the circuit is the same as that of a single cell.
- The total current flowing in the circuit splits up and flows through each cell.
- The internal resistance of the circuit is very low.
- More current can be made available for a longer time under low voltage.
Electric Current:
Electric current is the flow of electric charges. Current is the quantity of charge that flows through a conductor in a circuit in one second.