Handwritten Notes Physics Class- 12 Unit- 2 Alternating Current Notes Pdf Here
Aniket Ncert July 30, 2021
General Introduction:-
George Westinghouse
(1846 – 1914) A leading
proponent of the use of
alternating current over
direct current. Thus,
he came into conflict
with Thomas Alva Edison,
an advocate of direct
current. Westinghouse
was convinced that the
technology of alternating
current was the key to
the electrical future.
He founded the famous
Company named after him
and enlisted the services
of Nicola Tesla and
other inventors in the
development of alternating
current motors and
apparatus for the
transmission of high
tension current, pioneering
in large scale lighting.
Question:- A lamp is connected in series with a capacitor. Predict
your observations for dc and ac connections. What happens in each
case if the capacitance of the capacitor is reduced?
Answer:- When a dc source is connected to a capacitor, the capacitor
gets charged and after charging no current flows in the circuit and
the lamp will not glow. There will be no change even if C is reduced.
With ac source, the capacitor offers capacitative reactance (1/ωC )
and the current flows in the circuit. Consequently, the lamp will shine.
Reducing C will increase reactance and the lamp will shine less brightly
than before
