i have a question

what is the difference in brightness when two lights set in series is compared with the brightness one light in a circuit(series)?

AND

What is the difference in brightness when two lights set in parallel is compared with the brightness of one light in a circuit

i would be really thankful if you can answer my question. my e-mail is mercury_yang@hotmail.com

 

Hi
U may be aware that light bulbs have 2 specifications for working at optimum efficiency:-
1. Power Rating in watts (50W, 40 W etc) say W watts
2. Voltage rating in volts ( 230V, 110V etc)say V volts

It means that when a light bulb is connected across a potential difference of V volts(as specified) it provides a power output of W watts.
So connecting 2 bulbs in series across a potential difference of V volts, 0.5V volts is dropped across each bulb. Therefore each bulb only work to half their specified efficiency and produce a brightness that is half the optimum brightness

On connecting the 2 bulbs in parallel V volts is dropped across each bulb thus producing an output equal to the specified output in each bulb.

Hope this helps u.