# Electrical devices in parallel

The supply voltage to a room is $$\SI {120}{\volt}$$. The resistance of the lead wires is $$\SI {6}{\ohm}$$. A $$\SI {60} {\watt}$$ bulb is already switched on. What is the decrease of voltage across the bulb, when a $$\SI {240}{\watt}$$ heater is switched on in parallel to the bulb? if ur answer is V, give [V], [.] represents the greatest integer function.

Note: The combined resistance of the lead wires is $$\SI{6}{\ohm}$$ (since there are two of them).

Here supply voltage is taken as rated voltage.

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