For the given input voltage waveform Vin (t), the output voltage waveform V0(t), across the capacitor is correctly depicted by:
(A)(see structure)✓ Correct
(B)(see structure)
(C)(see structure)
(D)(see structure)
Answer: (A)
Solution
The resistor and capacitor form a low-pass combination with time constant τ=RC=10μs, which is comparable to the time over which the input changes. The capacitor voltage cannot follow the sharp steps of the input instantly; instead it climbs or falls exponentially towards whatever level the input currently holds, with the rounding set by τ. Over each segment of the input the output approaches the input value along an exponential charging curve, so the output is the smoothed, exponentially lagging version of the input rather than a faithful copy of its square edges.
JEE Main · 2020 · 06 Sep 2020 · Shift 1 · Single correct option
