# Physics GCSE question

Please could I have help on the highlighted part of this question? Since both lamps are exactly the same and have the same resistance, surely the voltage is spilt evenly so both x and y have the same brightness? Thank you!
(edited 1 year ago)
since you have less lamps in y,there would be less resistance,as resistance in series circuit is R1+R2+R3.......,so using the equation p=v^2/R,the value of p (power) would be greater for each lamp
physics sure is fun huh?
(edited 1 year ago)
Original post by Ashirs
Please could I have help on the highlighted part of this question? Since both lamps are exactly the same and have the same resistance, surely the voltage is spilt evenly so both x and y have the same brightness? Thank you!

In a series circuit, voltage is split evenly between components that have the same resistance. As there are more bulbs in lamp X than in lamp Y, the voltage of each bulb in circuit X is lower than the voltage of each bulb in circuit Y because the same number of volts is being shared between a greater number of components. Because each bulb in lamp Y has a greater voltage than each bulb in lamp X, a bulb in lamp Y will be brighter than a bulb in lamp X. Greater voltage = brighter. Hope that helps!
Original post by scar-the-queen
In a series circuit, voltage is split evenly between components that have the same resistance. As there are more bulbs in lamp X than in lamp Y, the voltage of each bulb in circuit X is lower than the voltage of each bulb in circuit Y because the same number of volts is being shared between a greater number of components. Because each bulb in lamp Y has a greater voltage than each bulb in lamp X, a bulb in lamp Y will be brighter than a bulb in lamp X. Greater voltage = brighter. Hope that helps!

Original post by samerchafte
since you have less lamps in y,there would be less resistance,as resistance in series circuit is R1+R2+R3.......,so using the equation p=v^2/R,the value of p (power) would be greater for each lamp

But since the resistance of the bulbs are the same, how would the resistance of Lamp Y be less if it is 350 ohms?
Original post by samerchafte
physics sure is fun huh?

….
Apart from the fact that I am taking it for a level
Original post by Ashirs
But since the resistance of the bulbs are the same, how would the resistance of Lamp Y be less if it is 350 ohms?

In a series circuit the total resistance of the circuit is calculated by adding the resistances of each component in the circuit. Lamp X would have a total resistance of 7 x 390 = 2730 ohms because there are 7 bulbs in the lamp each of which have a resistance of 390 ohms. Lamp Y would have a total resistance of 5 x 390 = 1950 ohms because there are 5 bulbs in the lamp each of which have a resistance of 390 ohms. I hope that makes more sense.
(edited 1 year ago)
Original post by scar-the-queen
In a series circuit the total resistance of the circuit is calculated by adding the resistances of each component in the circuit. Lamp X would have a total resistance of 7 x 390 = 2730 ohms because there are 7 bulbs in the lamp each of which have a resistance of 390 ohms. Lamp Y would have a total resistance of 5 x 390 = 1950 ohms because there are 5 bulbs in the lamp each of which have a resistance of 390 ohms. I hope that makes more sense.

Ohh yess that makes much more sense, thank you very much!!
Original post by Ashirs
Ohh yess that makes much more sense, thank you very much!!

Glad I could help!