NEET Physics Dual Nature of Matter and Radiation MCQs

In Lenard's experiment, ultraviolet light of wavelength 200 nm is incident on a metal surface. The stopping potential is found to be 4V. If the wavelength is increased to 300 nm, what will be the new stopping potential? (Take $h = 6.63 imes 10^{-34}$ Js, $c = 3 imes 10^8$ m/s, $e = 1.6 imes 10^{-19}$ C)

What is the de Broglie wavelength of an electron with momentum $10^{-24} kg \cdot m/s$? (Planck's constant $h = 6.626 imes 10^{-34} J \cdot s$)

The 'h' in Einstein's photoelectric equation stands for:

A photosensitive material has a work function of 2.0 eV. What is the minimum frequency of incident light required to emit photoelectrons?

How many photons are emitted by a laser source of $5 imes {10^{ - 3}}\;{\rm{W}}$ operating at 632.2 nm in 2s?

The work function of Cesium metal is 2.15 eV. When light of frequency $6 imes {10^{14}}\,Hz$ is incident on metal surface, photoemission occurs. Maximum kinetic energy of emitted photon electron will be

Consider an electron $\left( {m = 9.1\,\, imes \,\,{{10}^{ - 31}}\,\,kg} \right)$ confined by electrical forces to move between two rigid walls separated by $1.0\,\, imes \,\,{10^{ - 9}}\,\,metre$, which is about five atomic diameters. The quantized energy value for the lowest stationary state is

If $V$ be the accelerating voltage, then the maximum frequency of continuous $X$-rays is given by

The linear momentum of photon is $p$. The wavelength of photon is $\lambda \;,$ then ($h$ is Planck constant)

If $V$ be the accelerating voltage, then the maximum frequency of continuous $X$-rays is given by