Question 712: Current Electricity

Question

Two 220 volt, 100 watt bulbs are connected first in series and then  in parallel. Each time the combination is connected to a 220 volt a.c. supply line. The power drawn by the combination in each case respectively will be

Accepted Answer

$$R = {{{V^2}} \over P} = {{220 	imes 220} \over {100}} = 484\Omega $$
In series, R
eq
= 484 + 484 = 968 $$\Omega $$
$$ 	herefore {P_{eq}} = {{{V^2}} \over {968}} = {{220 	imes 220} \over {968}} = 50\,watt$$
In parallel, $${R_{eq}} = 242\Omega $$
$$ 	herefore {P_{eq}} = {{{V^2}} \over {242}} = {{220 	imes 220} \over {242}} = 200\,watt$$

Answer

50 watt, 100 watt

Answer

100 watt, 50 watt

Answer

200 watt, 150 watt

Answer

50 watt, 200 watt

Current Electricity

Two 220 volt, 100 watt bulbs are connected first in series and then in parallel. Each time the combination is connected to a 220 volt a.c. supply line. The power drawn by the combination in each case respectively will be

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