Which of the following is NOT correct in the case of the output obtained from a full wave rectifier?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → It is continuous output.
A full-wave rectifier passes both halves of the input cycle through the load in the same direction. The output current therefore never reverses, but its value rises from zero to the peak and falls back to zero in every half-cycle: it is a pulsating d.c., not a smooth, steady d.c. A filter (for example, a capacitor across the load) is needed to make it nearly steady.
Option (1) It is unidirectional output. — A correct description. Both half-cycles drive current through the load in the same direction.
Option (2) It is pulsating output. — A correct description. The output rises and falls between zero and the peak value in every half-cycle.
Option (3) Its ripple frequency is twice the input frequency. — A correct description. The output pattern repeats every half-cycle of the input, so for a 50 Hz input the ripple frequency is 100 Hz.
Option (4) It is continuous output. — Not a correct description. The output is not a continuous, steady d.c.; its value keeps varying and drops to zero twice in every cycle of the input.
NCERT (2026-27):
Application of Junction Diode as a Rectifier – “… The rectified voltage is in the form of pulses of the shape of half sinusoids. Though it is unidirectional it does not have a steady value. To get steady dc output from the pulsating voltage normally a capacitor is connected across the output terminals (parallel to the load RL).”