All Exams Test series for 1 year @ ₹349 only
Question

The reading of the ammeter ($A$) in steady state in the following circuit (assuming negligible internal resistance of the ammeter) is _______ A.

The correct answer is
2

To determine the reading of the ammeter in steady state, we need to analyze the circuit shown in the image. Here are the steps involved:

  1. In the steady state, a capacitor behaves like an open circuit for DC. Therefore, the 10 μF capacitor can be replaced by an open circuit.
  2. After replacing the capacitor with an open circuit, observe the modified circuit. The branches containing the 4 Ω resistor and the capacitor are open, meaning no current flows through this path.
  3. Now, the circuit simplifies to a combination of resistors in series and parallel.
  4. The 8 Ω resistor and the 8 Ω resistor in parallel with the ammeter form a series circuit with the voltage source.
  5. The equivalent resistance of two parallel 8 Ω resistors is: \(R_{\text{eq}} = \frac{8 \times 8}{8 + 8} = 4 \, \Omega\)
  6. The total resistance in the circuit is a combination of 1 Ω, 8 Ω, and the equivalent resistance of 4 Ω, resulting in: \(R_{\text{total}} = 1 + 8 + 4 = 13 \, \Omega\)
  7. Using Ohm's Law, the total current supplied by the battery is: \(I = \frac{V}{R_{\text{total}}} = \frac{10}{13} \, \text{A}\)
  8. This total current is divided equally between the two parallel branches, each having an 8 Ω resistor. Therefore, the current through the ammeter is: \(I_{\text{ammeter}} = 2 \, \text{A}\)

Hence, the reading of the ammeter in steady state is \(2\) A.

Was this answer helpful?

Similar Questions

  1. The electric field of a plane electromagnetic wave, travelling in an unknown non-magnetic medium is given by,
    $E_y = 20 \sin(3 \times 10^6 x - 4.5 \times 10^{14} t) \text{ V/m}$
    (where x, t and other values have S.I. units). The dielectric constant of the medium is _________.
    (speed of light in free space is $3 \times 10^8 \text{ m/s}$)
  2. A conducting circular loop is rotated about its diameter at a constant angular speed of 100 rad/s in a magnetic field of 0.5 T perpendicular to the axis of rotation. When the loop is rotated by $30^\circ$ from the horizontal position, the induced EMF is 15.4 mV. The radius of the loop is _________ mm.
    $\left(\text{Take } \pi = \frac{22}{7}\right)$
  3. A cylindrical conductor of length 2 m and area of cross-section $0.2 \text{ mm}^2$ carries an electric current of 1.6 A when its ends are connected to a 2 V battery. Mobility of electrons in the conductor is $\alpha \times 10^{-3} \text{ m}^2\text{/V.s}$. The value of $\alpha$ is :
    (electron concentration $= 5 \times 10^{28} \text{/m}^3$ and electron charge = $1.6 \times 10^{-19} \text{ C}$)
  4. A short bar magnet placed with its axis at $30^\circ$ with an external field of 800 Gauss, experiences a torque of 0.016 N.m. The work done in moving it from most stable to most unstable position is $\alpha \times 10^{-3} \text{ J}$. The value of $\alpha$ is ______.
  5. A regular hexagon is formed by six wires each of resistance $r \text{ }\Omega$ and the corners are joined to the centre by wires of same resistance. If the current enters at one corner and leaves at the opposite corner, the equivalent resistance of the hexagon between the two opposite corners will be
  6. Three parallel plate capacitors each with area $A$ and separation $d$ are filled with two dielectric ($k_1$ and $k_2$) in the following fashion. Which of the following is true? ($k_1 > k_2$)

  7. Two identical circular loops $P$ and $Q$ each of radius $r$ are lying in parallel planes such that they have common axis. The current through $P$ and $Q$ are $I$ and $4I$ respectively in clockwise direction as seen from $O$. The net magnetic field at $O$ is:

  8. A moving coil galvanometer of resistance $100 \text{ }\Omega$ shows a full scale deflection for a current of $1 \text{ mA}$. The value of resistance required to convert this galvanometer into an ammeter, showing full scale deflection for a current of $5 \text{ mA}$, is _______ $\Omega$
  9. A capacitor $C$ is first charged fully with potential difference of $V_0$ and disconnected from the battery. The charged capacitor is connected across an inductor having inductance $L$. In $t\text{ s}$ $25\%$ of the initial energy in the capacitor is transferred to the inductor. The value of $t$ is __________ $\text{s}$.
  10. The charge stored by the capacitor $C$ in the given circuit in the steady state is __________ $\mu\text{C}$.


Important Questions from Electricity and Magnetism

  1. The electric field of a plane electromagnetic wave, travelling in an unknown non-magnetic medium is given by,
    $E_y = 20 \sin(3 \times 10^6 x - 4.5 \times 10^{14} t) \text{ V/m}$
    (where x, t and other values have S.I. units). The dielectric constant of the medium is _________.
    (speed of light in free space is $3 \times 10^8 \text{ m/s}$)
  2. A conducting circular loop is rotated about its diameter at a constant angular speed of 100 rad/s in a magnetic field of 0.5 T perpendicular to the axis of rotation. When the loop is rotated by $30^\circ$ from the horizontal position, the induced EMF is 15.4 mV. The radius of the loop is _________ mm.
    $\left(\text{Take } \pi = \frac{22}{7}\right)$
  3. A cylindrical conductor of length 2 m and area of cross-section $0.2 \text{ mm}^2$ carries an electric current of 1.6 A when its ends are connected to a 2 V battery. Mobility of electrons in the conductor is $\alpha \times 10^{-3} \text{ m}^2\text{/V.s}$. The value of $\alpha$ is :
    (electron concentration $= 5 \times 10^{28} \text{/m}^3$ and electron charge = $1.6 \times 10^{-19} \text{ C}$)
  4. A short bar magnet placed with its axis at $30^\circ$ with an external field of 800 Gauss, experiences a torque of 0.016 N.m. The work done in moving it from most stable to most unstable position is $\alpha \times 10^{-3} \text{ J}$. The value of $\alpha$ is ______.
  5. A regular hexagon is formed by six wires each of resistance $r \text{ }\Omega$ and the corners are joined to the centre by wires of same resistance. If the current enters at one corner and leaves at the opposite corner, the equivalent resistance of the hexagon between the two opposite corners will be
Need Expert Advice?
More Questions from JEE Main

Start Your Preparation with Prepp Mobile App

Download the app from Google Play & App Store
Download the app from Google Play & App Store
Prepp Mobile App