Question

In a series circuit with three bulbs,
a.

there are many paths for the current to take.
b.

the remaining two bulbs are not affected if one bulb burns out.
c.

all of the bulbs become dimmer as more bulbs are added.
d.

a switch is never used.

Answer 1

Any ideas at all? Some should be easy to eliminate.

Answer 2

well it is D.. but it depends on what kind of light bulbs you use. If you were to replace the the bulbs with normal resistors, the current would decrease therefore the heat produced by each resistor would also decrease.. means less light too..

Answer 3

You can use the two equations to find out the answer, first the one to find out the power P=U X I
I = U/R
when you add more resistance to the circuit, that equals less amperes.. electricity flow.. so less power too >_> I think.. not sure.. someone back up here.

Answer 4

I would say the answer is c.
Notice that the current in the circuit is the same everywhere and is equal to:
\[I=\frac{ V }{ R_{eff} }\]
The voltage drop V across the circuit is equivalent to the voltage across the power source.
The effective Resistance is the addition of the resistances of each bulb since it's a series circuit. Increasing the number of bulbs, increases the resistance and hence reduces the current I.
Reducing the current reduces the power that is available for the bulbs, since
\[P=IV\]
Therefore, increasing the number of bulbs in a series circuit will dim all the bulbs.