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Connect a pair of lamps in series and you draw current from the connected battery. Connect the same lamps in parallel and you drawA) the same current.B) more current.C) less current.D) sometimes more, sometimes less.

Respuesta :

Answer:

B) more current.

Explanation:

When two lamps are connected in series then we have

[tex]R = R_1 + R_2[/tex]

now let the two lamps are identical

so we have

[tex]R_1 = R_2 = R[/tex]

now the total resistance of the lamps is given as

[tex]R_{eq} = R + R[/tex]

now the current in that case is given as

[tex]i = \frac{V}{R_{eq}}[/tex]

[tex]i = \frac{V}{2R}[/tex]

Now when lamps are connected in parallel

net resistance of two lamps is given as

[tex]\frac{1}{R_eq} = \frac{1}{R} + \frac{1}{R}[/tex]

so now we have

[tex]\frac{1}{R_{eq}} = \frac{2}{R}[/tex]

so we have

[tex]R_{eq} = \frac{R}{2}[/tex]

so now the current through the battery will be

[tex]i = \frac{V}{R/2} = \frac{2V}{R}[/tex]

So current will be more when two lamps are connected in parallel

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