Embibe Experts Solutions for Chapter: Dual Nature of Matter and Radiation, Exercise 2: BEGINNER'S BOX - 2

A light beam of power $1.5 \mathrm{mW}$ and $400 \mathrm{nm}$ wavelength incident on a cathode. If quantum efficiency is $0.1 \%$ then, find out obtained photocurrent and number of photoelectrons per second.

A metallic surface of the work function $h\nu$ is illuminated by a radiation beam of frequency $5\nu$. The stopping potential observed is $X$. What will be stopping potential if the surface is illuminated by radiation of $7\nu$ frequency?

The kinetic energy of the fastest moving photoelectron from a metal of work function $2.8 \mathrm{eV}$ is $2 \mathrm{eV}$. If the frequency of light is doubled, then find the maximum kinetic energy of the photoelectron.

A monochromatic light incident on the metal $A$ having threshold frequency ${\nu }_0$. It emits photoelectrons of maximum kinetic energy $K$. Now the incident frequency is made three times and falls on a metal $B$ having threshold frequency $2{\nu }_0$. What will the maximum kinetic energy of photoelectrons be emitted by metal $B$?

If the light of wavelength $4000 \stackrel{\circ }{\mathrm{A}}$ falls on a metal that has a stopping potential $1.4 \mathrm{volt}$ against photoelectric emission, then what is the work function of the metal. [Take $h=6.6\times {10}^{-34} \mathrm{J} \mathrm{s}$ and $c=3\times {10}^8 \mathrm{m} {\mathrm{s}}^{-1}$]

X-rays are produced in a X-ray tube by electrons accelerated through an electric potential difference of 50.0 kV. An electron makes three collisions in the target before coming to rest and loses half of its remaining kinetic energy in each of the first two collisions. Determine the wavelength of the resulting photons. (Neglect the recoil of the heavy target atoms)

Voltage applied across the coolidge tube is 25 kV. What is kinetic energy of electron striking at the target and cut-off wavelength of X-ray obtained from the tube ?

If applied potential across the X-ray tube is made $\frac{2}{5}$ time then minimum wavelength of X-rays is shifted by $\stackrel{\mathrm{o}}{1 \mathrm{A}}$. Find the original values of applied potential and minimum wavelength.