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a) Rectification (smoothing circuits)
In the conversion of alternating current to direct current using diodes, a capacitor is used to maintain a high d.c. voltage. This is called smoothing or rectification.
b) Reduction of sparking in the induction coil
A capacitor is included in the primary circuit of the induction coil to reduce sparking.
c) In tuning circuits
A variable capacitor is connected in parallel to an inductor in the tuning circuit of a radio receiver. When the capacitance of the variable capacitor is varied , the electrical oscillations between the capacitor and the inductor changes. If the frequency of oscillations is equal to the frequency of the radio signal at the aerial of the radio, that signal is received.
d) In delay circuits
Capacitors are used in delay circuits designed to give intermittent flow of current in car indicators.
e) In camera flash
A capacitor in the flash circuit of a camera is charged by the cell in the circuit. When in use, the capacitor discharges instantly to flash.
chrispohmomanyi answered the question on February 9, 2018 at 06:29
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