Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
Concepts Of Physics MCQ Edition [Volume 2]
Exam
Concepts Of Physics MCQ Edition [Volume 2]
Subject
Physics
Chapter
Electric Current in Conductors

Concepts Of Physics MCQ Edition [Volume 2] · Physics · Electric Current in Conductors

A capacitor with a capacitance of 500 is connected to a battery via...

A capacitor with a capacitance of 500μF500 \mu\text{F} is connected to a battery via a 10 kΩ10 \text{ k}\Omega resistor. Which of the following statements are true regarding the charge stored on the capacitor during the initial 5 s5 \text{ s}?

Options

  1. AIt is smaller than the charge stored in the subsequent 5000 s5000 \text{ s}.
  2. BIt is larger than the charge stored in the subsequent 50 s50 \text{ s}.
  3. CIt is larger than the charge stored in the subsequent 500 s500 \text{ s}.
  4. DIt is larger than the charge stored in the subsequent 5 s5 \text{ s}.

Correct answer

D. It is larger than the charge stored in the subsequent 5 s5 \text{ s}.

Step-by-step solution

The time constant of the RCRC circuit is given by τ=RC\tau = RC.

Substituting the given values:

τ=(10×103)×(500×10−6)=5 s\tau = (10 \times 10^3) \times (500 \times 10^{-6}) = 5 \text{ s}

The charge on the capacitor as a function of time is q(t)=q0(1−e−t/τ)q(t) = q_0(1 - e^{-t/\tau}), where q0q_0 is the maximum steady-state charge.

The charge stored during the initial 5 s5 \text{ s} (t=τt = \tau) is:

q1=q(5)−q(0)=q0(1−e−1)≈0.632q0q_1 = q(5) - q(0) = q_0(1 - e^{-1}) \approx 0.632 q_0

The maximum possible charge that can be stored in all subsequent time (t=5 st = 5 \text{ s} to t→∞t \to \infty) is:

qremaining=q(∞)−q(5)=q0−0.632q0=0.368q0q_{\text{remaining}} = q(\infty) - q(5) = q_0 - 0.632 q_0 = 0.368 q_0

Since 0.632q0>0.368q00.632 q_0 > 0.368 q_0, the charge stored in the initial 5 s5 \text{ s} is strictly greater than the total charge stored in any subsequent time interval, regardless of its duration.

Therefore, the charge stored in the initial 5 s5 \text{ s} is larger than the charge stored in the subsequent 5 s5 \text{ s}, 50 s50 \text{ s}, 500 s500 \text{ s}, and 5000 s5000 \text{ s}.
Practice Electric Current in Conductors on Quantrex Academy →

More from Electric Current in Conductors

The amount of charge passing through a cross-section of a wire in time t is given by Q(t)… Concepts Of Physics MCQ Edition [Volume 2]A discharge tube carries an electric current of 2.0 . Determine the amount of charge that… Concepts Of Physics MCQ Edition [Volume 2]The current flowing through a wire varies with time according to i = i_0 + α t , where… Concepts Of Physics MCQ Edition [Volume 2]A copper wire with a cross-section of 1.0 mm^2 carries a current of 1.0 A . Determine the… Concepts Of Physics MCQ Edition [Volume 2]An electron gun releases 2.0 × 10^ 16 electrons per second. Determine the electric… Concepts Of Physics MCQ Edition [Volume 2]The amount of charge passing through a cross-section of a wire in time t is Q(t) = At^2 +… Concepts Of Physics MCQ Edition [Volume 2]A uniform wire having a resistance of 100 Ω is melted and recast into a new wire whose… Concepts Of Physics MCQ Edition [Volume 2]Determine the required length of a copper wire having a cross-sectional area of 0.01 mm^2… Concepts Of Physics MCQ Edition [Volume 2] Full Electric Current in Conductors list All Concepts Of Physics MCQ Edition [Volume 2] PYQs