Answer to Question #326650 in Electric Circuits for Leo

Question

1. You connect a number of identical light bulbs to a flashlight battery. (a) What happens to the brightness of each bulb as more and more bulbs are added to the circuit if you connect them (i) in series and (ii) in parallel? (b) Will the battery last longer if the bulbs are in series or in parallel? Explain your reasoning.

Answer 1

a)

For series connection resistance of circuit is bigger. So, by Ohm's Law (I=U/R), the brightness of each bulb is more in case of parallel circuit.

b)

Power formula: $P=UI$

Series circuit of bulbs requires more power. So, the battery last longer if the bulbs are in parallel.