Question

Question below:

Answer 1

@Vincent-Lyon.Fr

Answer 2

I got the supply voltage as

\[V=\sqrt{180R}\]

Answer 3

Voltage for individual resistor will be multiplied by 3 and current too.
So power will be multiplied by 9.

Answer 4

How can we reach such a conclusion?

Answer 5

For each lamp: voltage = E/3 and current = I = E/3R => power = E²/9R

If in parallel:
For each lamp: voltage = E and current = E/R => power = E²/R

Answer 6

first, solve the voltage value in series.
then use that value to solve for the Power consumed using the same V and R

Answer 7

Oh okay that makes more sense. What if they were not identical. How do I proceed then?

Answer 8

well V and I I mean

Answer 9

if they are not identical then it would be difficult without giving more information

Answer 10

Do the same reasoning for each lamp. But you can solve it only if you know the values of the resistances.

Answer 11

that is a big IF, which I denoted that more information will be needed

Answer 12

Oh okay. Thanks for the help both of you :)

Answer 13

One more question by the way. Can I add power=P1+P2+P3 when in series?

Answer 14

Each resistor has its own power. Powers will add up, whether in series, in parallel or in any other type of mesh.

Answer 15

So P=P1+P2+P3 is right?

Answer 16

Of course.

Answer 17

Okay :-)