List of top Physics Questions on Modern Physics asked in TS EAMCET

When electromagnetic radiation of wavelength 310 nm falls on the surface of a metal having work function 3.55 eV, the velocity of photoelectrons emitted is \( x \times 10^5 \text{ms}^{-1} \). The value of \( x \) is (Nearest integer) (\( m_e = 9 \times 10^{-31} \text{kg} \))

An electromagnetic radiation of wavelength 331.5 nm is made to strike the surface of a metal. Electrons are emitted with a kinetic energy of \(1.2 \times 10^5\) J mol\(^{-1}\). The work function (in eV) of the metal is (h=\(6.63 \times 10^{-34}\) Js, \(N_A = 6 \times 10^{23}\) mol\(^{-1}\))

The work done to accelerate an electron from rest so that it can have a de Broglie wavelength of 6600 Å is nearly (Planck's constant = \(6.6 \times 10^{-34}\) Js and mass of electron = \(9 \times 10^{-31}\)kg)

If the total energy of an electron in an orbit is positive, then

Match the "Technology" given in List-1 with the "Principle of Physics" given in List-2.

If the difference in the frequencies of the first and second lines of Lyman series of hydrogen atom is f, then the difference in frequencies of the first and second lines of Balmer series of hydrogen atom is

Photons of energy 4.5 eV are incident on a photosensitive material of work function 3 eV. The de Broglie wavelength associated with the photoelectrons emitted with maximum kinetic energy is nearly

For any fixed distance, the electromagnetic force between two protons is \( 10^n \) times of the gravitational force between them. Then \( n = \)

Identify the incorrect statement from the following?

In $\beta^-$ decay, a neutron transforms into a proton within the nucleus according to the equation:
neutron $\to$ proton + $\beta^-$ + $x$
In this equation the particle represented by 'x' is

Two radioactive substances A and B have same number of initial nuclei. If the half-lives of A and B are 1.5 days and 4.5 days respectively, then the ratio of the number of nuclei remaining in A and B after 9 days is

\(10^{10}\) electrons enter the emitter of a junction transistor in a time of \(0.4\ \mu\text{s}\). If \(5%\) of the electrons are lost in the base, then the collector current is

An electron in n-region of a p-n junction moves towards the junction with a speed of \(5 \times 10^5\ \text{ms}^{-1}\). If the barrier potential of the junction is \(0.45\ \text{V}\), then the speed with which the electron enters the p-region after penetration through the barrier is
(Charge of the electron \(= 1.6 \times 10^{-19}\ \text{C}\) and mass of the electron \(= 9 \times 10^{-31}\ \text{kg}\))

Coaxial cable, a widely used wire medium offers an approximate frequency bandwidth of

The electron in hydrogen atom undergoes transition from higher orbits to an orbit of radius 476.1 pm. This transition corresponds to which of the following series?

When a photosensitive material is illuminated by photons of energy 3.1 eV, the stopping potential of the photoelectrons is 1.7 V. When the same photosensitive material is illuminated by photons of energy 2.5 eV, the stopping potential of the photoelectrons is

The ratio of the kinetic energies of the electrons in the third and fourth excited states of hydrogen atom is

Bose-Einstein statistics is applicable to particles with