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

A load $W$ produces an extension of $1 mm$ in a thread of radius $r$ : Now if the load is made $4 W$ and radius is made $2 r$ all other things remaining same, the extension will become
→
Equal masses of water and a liquid of density 2 are mixed together, then the mixture has a density of
→
(USS 133) Indium impurity in germanium makes
→
If the temperature increases, then what happens to the frequency of the sound produced by the organ pipe
→
The wavelength of de-Broglie wave is $2 \mu \mathrm{m}$, then its momentum is $(h$ $\left.=6.63 \times 10^{-34} \mathrm{~J}-\mathrm{s}\right)$
→
A convex lens forms a real image of a point object placed on its principal axis. If the upper half of the lens is painted black, the image will
→
A particle of mass $m$ moving eastward with a speed $v$ collides with another particle of the same mass moving northward with the same speed $v$. The two particles coalesce on collision. The new particle of mass $2 \mathrm{~m}$ will move in the north-easterly direction with a velocity
→
If a body $A$ of mass $M$ is thrown with velocity $V$ at an angle of $30^{\circ}$ to the horizontal and another body $B$ of the same mass is thrown with the same speed at an angle of $60^{\circ}$ to the horizontal. The ratio of horizontal range of $A$ to $B$ will be
→
Two coils of self inductance $L_1$ and $L_2$ are placed closer to each other so that total flux in one coil is completely linked with other. If $M$ is mutual inductance between them, then
→
The resistivity of a potentiometer wire is $40 \times 10^{-8} \mathrm{ohm}-\mathrm{m}$ and its area of cross-section is $8 \times 10^{-6} \mathrm{~m}^2$. If $0.2\  \mathrm{amp}$ current is flowing through the wire, the potential gradient will be
→