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# Problem: The lightbulbs in the circuits below are identical with the same resistance R. Which circuit produces more light? (brightness ⇐ ⇒ power)a) circuit Ib) circuit IIc) both the samed) It depends on R

###### FREE Expert Solution

In a parallel connection, as shown in circuit I, the voltage is the same for both bulbs.

The light bulbs have the same resistance.

The power of each bulb will be given by:

Pp = V2/R

However, suppose the bulbs are connected in series like in the second case, the current through each bulb will be the same as the current through the entire circuit.

This current is given by:

$\mathbit{i}\mathbf{=}{\mathbit{i}}_{\mathbf{1}}\mathbf{=}{\mathbit{i}}_{\mathbf{2}}\mathbf{=}\frac{\mathbf{V}}{{\mathbf{R}}_{\mathbf{e}\mathbf{q}}}$

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###### Problem Details

The lightbulbs in the circuits below are identical with the same resistance R. Which circuit produces more light? (brightness ⇐ ⇒ power)

a) circuit I

b) circuit II

c) both the same

d) It depends on R

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Power in Circuits concept. You can view video lessons to learn Power in Circuits. Or if you need more Power in Circuits practice, you can also practice Power in Circuits practice problems.