GEOLOGY

Detailed explanation-1: -Increasing the number of bulbs in a series circuit decreases the brightness of the bulbs. In a series circuit, the voltage is equally distributed among all of the bulbs. Bulbs in parallel are brighter than bulbs in series. In a parallel circuit the voltage for each bulb is the same as the voltage in the circuit.

Detailed explanation-2: -The effect of adding a second bulb in series is to increase the overall resistance of the circuit. The resistance previously provided by the thin filament wire of just one bulb is now doubled due to the presence of two. This increase in resistance reduces the drift speed of charged particles everywhere in the circuit.

Detailed explanation-3: -When in series, bulbs become dimmer as the potential difference is shared equally across the bulbs. The current reads the same for each component. In parallel, each branch shows the same potential difference, so the bulbs on one branch will have the same relative brightness.

Detailed explanation-4: -For bulbs that are added in parallel, the additional bulb(s) will have the same amount of electric current flowing through and each bulb does not share the electric current. Hence, the brightness of bulb remains the same(Figure 6).

Detailed explanation-5: -Three identical electric bulbs are connected parallel to each other. On connecting their combination across a source of emf having stabilized voltage and negligible resistance, all bulbs glow with full brightness. Suddenly a bulb fuses. The other bulbs will glow.