Download App

Electron, Photon, Photo-electric Effect and X-Rays — JEE physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 ScienceJEE physicsElectron, Photon, Photo-electric Effect and X-Rays1 Mark
MCQ
An $X$-ray machine has an accelerating potential difference of $25,000$ volts. By calculation the shortest wavelength will be obtained as $\left(h=6.62 \times 10^{-34} J-s e c ; \mathrm{e}=1.6 \times 10^{-19}\right.$ coulomb $)$
  • A
    $0.25 \mathring A$
  • ✓
    $0.50 \mathring A$
  • C
    $1.00 \mathring A$
  • D
    $2.50 \mathring A$
✓

Answer

Correct option: B.
$0.50 \mathring A$
$\lambda_{\text {min }}=\frac{h c}{e V}=\frac{12375}{V} \mathring A=0.495 \mathring A \ \approx 0.5 \mathring A$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "MCQ" from Electron, Photon, Photo-electric Effect and X-Rays→Electron, Photon, Photo-electric Effect and X-Rays — all question types→JEE physics STD 12 Science question papers→CBSE Board STD 12 Science question papers→CBSE Board question paper generator→

Similar questions

One mole of an ideal monoatomic gas is heated at a constant pressure of one atmosphere from $0^{\circ} \mathrm{C}$ to $100^{\circ} \mathrm{C}$. Then the change in the internal energy is
→
The kinetic energy acquired by a mass $m$ in travelling a certain distance $d$ starting from rest under the action of a constant force is directly proportional to
→
In the state of weightlessness, a capillary tube is dipped in water, then water
→
The potential energy of a particle executing S.H.M. is 2.5 J, when its displacement is half of amplitude. The total energy of the particle be
→
A neutron having mass of $1.67 \times 10^{-27} \mathrm{~kg}$ and moving at $10^8 \mathrm{~m} / \mathrm{s}$ collides with a deutron at rest and sticks to it. If the mass of the deutron is $3.34 \times 10^{-27} \mathrm{~kg}$ then the speed of the combination is
→
A shell initially at rest explodes into two pieces of equal mass, then the two pieces will
→
The resistivity of a wire depends on its
→
The minimum magnifying power of a telescope is $\mathcal{M}$, If the focal length of its eye lens is halved, the magnifying power will become
→
The minimum intensity of light to be detected by human eye is $10^{-10} \mathrm{~W} / \mathrm{m}^2$. The number of photons of wavelength $5.6 \times 10^{-7} \mathrm{~m}$ entering the eye, with pupil area $10^{-6} \mathrm{~m}^2$, per second for vision will be nearly
→
The minimum wavelength of photon is $5000 \mathring A$, its energy will be
→