List of practice Questions

A long straight wire of circular cross-section of radius \( a \) is carrying a steady current. The current is distributed uniformly across the cross-section of the wire. The ratio of the magnetic fields at points \( 0.5a \) and \( 1.5a \) from the centre of the wire is:
A galvanometer having 30 divisions has a current sensitivity of \(0.0625 \, \frac{\text{div}}{\mu\text{A}}\). If it is converted into a voltmeter to read a maximum of 6 V, then the resistance of that voltmeter is:
An AC source of internal resistance \( 10^3 \ \Omega \) is connected to a transformer. The ratio of the number of turns in the primary to the number of turns in the secondary to match the source to a load resistance of \( 10 \ \Omega \) is
If an inductor of inductance \(0.5 \, \mu H\) is connected to an AC source of frequency 70 MHz and voltage 3.3 V, then the current through the inductor is:
If an electron and a proton enter normally into a uniform magnetic field with equal kinetic energies, then:
If the formation of a real image using a biconvex lens of material of refractive index 1.5 is shown in the figure. If this setup is immersed in water (refractive index = $\frac{4}{3}$), then
formation of a real image using
When a stretched string is vibrated simultaneously with a 440 Hz tuning fork, a beat frequency of 5 Hz is produced. If the experiment is repeated with a tuning fork of 437 Hz, the beat frequency produced is 8 Hz. The frequency of the string is
A body is moving along a straight line under the influence of a constant power source. If the relation between the displacement (s) of the body and time (t) is \(s \propto t^x\), then \(x =\)
An electric dipole with dipole moment $2 \times 10^{-10}\, C \cdot m$ is aligned at an angle $30^\circ$ with the direction of a uniform electric field of $10^4\, N/C$. The magnitude of the torque acting on the dipole is
A velocity selector is to be constructed to select ions with a velocity of 6 km/s. If the electric field used is 400 V/m, then the magnetic field to be used is
A Carnot engine A working between temperatures 600 K and T (T \(<\) 600 K) and another Carnot engine B working between temperatures T (T \(>\) 400 K) and 400 K are connected in series. If the work done by both the engines is same, then T =
The stress-strain graph of two wires A and B is shown in the figure. If \(Y_A\) and \(Y_B\) are Young’s moduli of materials of wires A and B respectively, then
stress strain
The nature of the graph between the temperature in Fahrenheit and Celsius values is:
A force of 18 N is acting in the direction of motion of a body of mass 3 kg moving with a velocity of 2 ms\(^{-1}\). The velocity of the body when it displaces by 5 m is
The force required to stretch a steel wire of area of cross-section \(1 \ \text{mm}^2\) to double its length is
(Young’s modulus of steel \(= 2 \times 10^{11} \ \text{N/m}^2\))

If each resistance in the given figure is 9 $\Omega$, then the reading of the ammeter (A) is

If the linear momentum of a proton is changed by \(p_0\), then the de Broglie wavelength associated with the proton changes by 0.25%. Then the initial linear momentum of the proton is

In the given circuit, the potential difference across the plates of the capacitor \( C \) in steady state is

A Carnot engine A working between temperatures 600 K and T (T \(<\) 600 K) and another Carnot engine B working between temperatures T (T \(>\) 400 K) and 400 K are connected in series. If the work done by both the engines is same, then T =
A metallic disc of radius 0.3 m is rotating with a constant angular speed of \( 60 \, \text{rad s}^{-1} \) in a plane perpendicular to a uniform magnetic field of \( 5 \times 10^{-2} \, \text{T} \). The emf induced between a point on the rim and the centre of the disc is
The ratio of the orders of the spacings of nuclear energy levels and atomic energy levels is:
The voltage gain and the current amplification factor of a transistor in common emitter configuration are \( 300 \) and \( 60 \) respectively. If the collector resistance is \( 5 k\Omega \), then the base resistance is:
If the tension in the horizontal wire shown in the figure is 30 N, then the weight \( W \) and tension in the wire \( OA \) are respectively:
tension in the horizontal wire
The escape velocity of a body from a planet of mass \(M\) and radius \(R\) is 14 km/s. The escape velocity of the body from another planet having same mass and diameter \(8R\) (in km/s) is
In the given circuit, if \( A = 0 \), \( B = 1 \), and \( C = 1 \) are inputs, then the values of \( y_1 \) and \( y_2 \) are respectively
A=0B=1C=1