Physics · Electrostatics
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The time constant of an RC circuit during discharge is that time in which charge on plates, as compared to maximum charge
- A
25 percent
- B
50 percent
- C
63.3 percent
- D
36.8 percent
Explanation:
During the discharge of an RC circuit, the charge on the capacitor decreases exponentially according to the formula: Q(t) = Q₀e^(-t/RC), where Q(t) is the charge at time t, Q₀ is the initial charge, and RC is the time constant.
When t = RC (one time constant), Q(RC) = Q₀e^(-1) ≈ 0.368Q₀.
This means the charge remaining is approximately 36.8% of the initial charge.
25 percent: Incorrect calculation.
50 percent: Incorrect calculation.
63.3 percent: This is the percentage of charge remaining during charging, not discharging.
Explanation:
During the discharge of an RC circuit, the charge on the capacitor decreases exponentially according to the formula: Q(t) = Q₀e^(-t/RC), where Q(t) is the charge at time t, Q₀ is the initial charge, and RC is the time constant.
When t = RC (one time constant), Q(RC) = Q₀e^(-1) ≈ 0.368Q₀.
This means the charge remaining is approximately 36.8% of the initial charge.
Tagged under Physics · Electrostatics · 2023