List of top Questions asked in AP EAPCET

The frequency of light emitted during the \(n = 4 \to n = 2\) transition in hydrogen is \( \frac{3}{7} \) times that of which transition in Li atom?

The frequency suitable beyond the horizon communication using sky wave is:

The ratio of radii of 3rd and 6th Bohr’s orbits in a hydrogen atom is:

The values of \( Y \) and \( Z \) in the given logic circuit are:

The wavelength of the electron in the first orbit of hydrogen atom is \(3.3 \times 10^{-10} \, \text{m}\). The kinetic energy of the electron (in J) is: (Given: \( h = 6.6 \times 10^{-34} \, \text{Js}, \, m_e = 9.0 \times 10^{-31} \, \text{kg} \))

A \(70 \, \text{mH}\) inductor is connected to a \(220 \, \text{V}, 50 \, \text{Hz}\) AC supply. The RMS value of the current in the circuit is:

A short bar magnet placed with its axis at \(45^\circ\) with a uniform external magnetic field of \(28.3 \times 10^{-3} \, \text{T}\) experiences a torque of magnitude \(3.6 \times 10^{-5} \, \text{J}\). The magnitude of magnetic moment of the magnet is nearly:

The quantities that don’t change when a resistor connected to a battery is heated due to the current are:

An isosceles triangular current-carrying loop is kept perpendicularly in a uniform magnetic field \( \vec{B}_0 \) as shown in the figure. The force on the loop due to magnetic field is:

A metal loop of area \(10 \, \text{cm}^2\) is placed in a region such that its area vector points along \( \hat{k} \). The region contains a uniform magnetic field of magnitude \(1.73 \, \text{T}\) that points in the direction \( \hat{i} + \hat{j} + \hat{k} \). When the magnetic field is switched off, the field decreases to zero at a steady rate in 10 seconds. The magnitude of emf induced in the loop is:

A battery with a \(12\,\text{V}\) emf has an initial charge of \(80\,\text{A·h}\). If the potential across the terminals remains constant until it is fully discharged, how long can the battery deliver energy at a rate of \(120\,\text{W}\)?

A charged particle is moving in a uniform magnetic field and enters a lead layer, losing half of its kinetic energy. The radius of curvature of its path becomes:

A ray of light is incident at \(30^\circ\) from a medium of refractive index 2 into a medium of refractive index 1. Then the angle of refraction is:

Electric potential due to a space is given by: \[ \phi(x, y, z) = \phi_0 \cdot \frac{x_0}{x} \] where \( x_0 = 5\,\text{m}, \phi_0 = 8\,\text{V} \). Find the electric field at the point (10 m, 5 m, 5 m).

Among the following, the equation representing a progressive wave is:

In a space having electric field \( \vec{E} = A(x\hat{i} + y\hat{j}) \), the potential at point (10 m, 20 m) is zero. Then the potential at the origin is: (Given \( A = 10 \, \text{Vm}^{-2} \))

A beam of light reflects and refracts at the surface between air and glass. The index of refraction of the glass is \(1.4\). If the refracted and reflected rays are perpendicular to each other, then the angle of incidence in the air is:

A charge \( Q \) is to be divided between two objects. The values of the charges on the objects so that the electrostatic force between them will be maximum is:

A body cools down from \(75^\circ C\) to \(65^\circ C\) in 10 minutes. It will cool down from \(65^\circ C\) to \(55^\circ C\) in a time

A copper wire of length 2.4 m and an aluminum wire of length 0.7 m, both having diameter 2 mm, are connected end to end. When stretched by a load, the obtained elongation is found to be 0.6 mm. The applied load is
(Given: Young’s modulus of copper \( Y_C = 1.2 \times 10^{11} \, \text{Nm}^{-2} \), Young’s modulus of aluminum \( Y_A = 0.7 \times 10^{11} \, \text{Nm}^{-2} \))

The rms speed of oxygen at room temperature is about \(500 \, \text{m/s}\). The rms speed of hydrogen at the same temperature is about

Energy needed in breaking a liquid drop of radius \( R \), into \( n \) smaller drops each of radius \( r \), is
[ \( T \) - Surface tension of the liquid ]

An object of mass \(10 \, \text{kg}\) is released from rest in a liquid. If the object moves a distance of \(2 \, \text{m}\) while sinking in a time duration of \(1 \, \text{s}\), then the mass of the liquid displaced by the submerged object is (Given: Acceleration due to gravity \( g = 10 \, \text{m/s}^2 \))

A Carnot engine operating between temperatures \( T_H = 600\,K \) and \( T_C = 300\,K \), absorbs \( Q_H = 800 \, \text{J} \) of heat from the source. The mechanical work done per cycle is:

The angular momentum of a wheel having a rotational inertia of \( 0.2 \, \text{kg} \, \text{m}^2 \) about its symmetric axis decreases from \( 4 \) to \( 2 \, \text{kg} \, \text{m}^2 \, \text{s}^{-1} \) in \( 4 \, \text{s} \). The average power of the wheel is