1Resistors of 10 Ω, 20 Ω and 30 Ω are first joined in series with a 12 V battery, and then the same resistors are joined in parallel with the same battery. Calculate the current in both cases and compare them.
2In the series and parallel bulb circuits, what relationship do you find between \( V_1 \), \( V_2 \) and V, and between \( I_1 \), \( I_2 \) and I?
3What happens to the brightness when one more bulb is added to each circuit? Why?
4Derive the formula \( R = R_1 + R_2 + R_3 \) for resistors in series.
5Derive the formula \( \frac{1}{R} = \frac{1}{R_1} + \frac{1}{R_2} + \frac{1}{R_3} \) for resistors in parallel.
6Why are the lights, fans and television in a house connected in parallel?
7What is the drawback of joining decorative lights in series?
8Resistors of 5 Ω, 10 Ω and 15 Ω are joined in series with a 6 V battery. Find the current and the potential difference across each resistor.
9Two 4 Ω resistors are joined in parallel. What is the total resistance, and why is it less than 4 Ω?