Hello everybody,
I read in class 9 and am not experienced in parallel and series circuit.
First, I connect three identical filaments in series and then I connect three more in parallel to the lamp which is in the middle of the three lamps in series. If the power supply produces 20A and 15V, can you please tell me what the current and voltage across each lamp will be?
Thank You in advance.

 

Begin by drawing a circuit schematic. This helps to clarify what you are trying to say in words.

 

This is more of an electronics issue, so I have moved it to a more appropriate forum.

 

You better draw the Circuit diagram on paper, take its photograph, attach it to your post and then ask questions.

 

You talk about "filaments" and "lamps". Do you mean lamp bulbs in both cases?

If so, then if your final result 1 bulb that is in series with a parallel combination of four bulbs which, in turn, is in series with a final, sixth bulb.

If so, then

Q1) What is the current in each of the two series bulbs?

Q2) What is te sum of the curents in the four parallel bulbs?

Q3) What is the current in each of the parallel bulbs?

Q4) If the voltage across one of the parallel bulbs if Vo, what is the voltage across each of the two series bulbs?

Q5) What is the total voltage, in terms of Vo, across the entire sting of bulbs?

Q6) What is the voltage, in volts, across the entire string of bulbs?

Q7) What are the voltages, in volts, across each bulb?