List of top Physics Questions on Modern Physics asked in AP EAPCET

The work function of Mg, Cu, Ag, Li are \(3.7, 4.8, 4.3, 2.5\,\text{eV}\) respectively. A wavelength of \(300\,\text{nm}\) light is shined on them. The metals which undergo photoelectric effect are
Light of wavelength \(1000\AA\) incidents on a metal surface of work function \(6\,eV\). The maximum kinetic energy of photoelectrons is
Two identical photo cathodes receive light of frequencies \( f_1 \) and \( f_2 \). If the velocity of photo electrons (of mass m) coming out are respectively \( V_1 \) & \( V_2 \) then:
Sodium and Copper have work functions 2.3 eV and 4.5 eV respectively. Then the ratio of their threshold wavelengths is nearly:
Two identical parallel metal plates A and B, having fine holes at their centers are connected to a power supply as shown in the figure. An electron having energy 200 eV is directed to pass through these holes from A to B. The de Broglie wavelength of the electron when it comes out of plate B is:
Work function of a metallic surface is 5.01 eV. When a light of wavelength 2000Å falls on the metallic surface, it emits photo electrons. The potential difference required to stop the fastest photo electron is? (in Volt)
The de Broglie wavelength of a particle of mass $m$ moving with a velocity $v$ is given by
The work function of a metal depends on
An electron of specific charge \( \frac{e}{m} \) enters an electric field, \( \vec{E} = -E_0 \hat{i} \) at a time \( t = 0 \) with an initial velocity \( \vec{v}_1 \). If \( \lambda_0 \) is its initial de Broglie wavelength, then its de Broglie wavelength at a time ‘t’ is
If the angular momenta of electrons in two orbits of hydrogen atom are \( \frac{h}{\pi} \) and \( \frac{1.5h}{\pi} \), then the ratio of velocities of electrons in these two orbits is
(h – Planck’s constant)
If the half-life of a radioactive substance is 32 hours, then the fraction of the substance decayed in 4 days is
The wavelength of spectral line corresponding to electron transition \( n = 3 \) to \( n = 2 \) for \( \text{Li}^{2+} \) ion is \( \lambda \,\text{nm} \). What is the wavelength (in nm) corresponding to electron transition \( n = 4 \) to \( n = 1 \) for \( \text{He}^+ \) ion?
If a bullet of mass 2 g travels with velocity of 3 × 103 cm s-1, its wavelength (in m) is: (h = 6.6 × 10-34 Js)
The ratio of the radii of the nuclei of mass numbers 27 and 64 is:
The waves used for line of sight communication and satellite communication are:
Two light waves of wavelengths 600 nm and 200 nm are incident on a metal surface. The maximum velocity of photoelectrons produced due to one wavelength is \(\frac{1}{3}\) of the maximum velocity of the photoelectrons produced due to the other wavelength. Find the work function of the metal.
Light of wavelength \(1\ \text{nm}\) belongs to the following class of waves