a bulb and a capacitor are connected in series to A.C.source of variable frequency.how will the brightness of the bulb change on increasing the frequency of the A.C. source? give reason for your answer.
We know that Induced Emf from an emf source is given as E=NBAwsinwt where w=frequency of source
Now we Observe from the Expression that E is directly proportional to w, where w=2πf where f=frequency of source
Hence On increasing the frequency of AC source, emf increasing making the brightness of bulb more.
Hence Brightness of Bulb increases with increase in frequency of the source.