MCQ
The nuclear cross-section is measured in barn, it is equal to
- A${10^{ - 20}}\,{m^2}$
- B${10^{ - 30}}\,{m^2}$
- ✓${10^{ - 28}}\,{m^2}$
- D${10^{ - 14}}\,{m^2}$
✓
Answer
Correct option: C.
${10^{ - 28}}\,{m^2}$
c
Barn is the unit used to measure the very small area.
Barn is the unit used to measure the very small area.
$1 \text { Barn }=10^{-28}\, m ^2$
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
An iron rod of susceptibility $599$ is subjected to a magnetising field of $1200\, Am ^{-1}$. The permeability of the material of the rod is
→$\left(\mu_{0}=4 \pi \times 10^{-7}\, T\, m\, A ^{-1}\right)$
The total internal energy of two mole monoatomic ideal gas at temperature $T=300\,K$ will be ...........$J$.
→$\text { (Given } R =8.31\,J / mol.K )$
Two identical narrow slits $S_1$ and $S_2$ are illuminated by light of wavelength $\lambda$ from a point source $P$. If, as shown in the diagram above the light is then allowed to fall on a screen, and if $n$ is a positive integer, the condition for destructive interference at $Q$ is that
→Rank the value of $\oint {\vec B.\overrightarrow {dl} } $ for the closed paths shown in figure from the smallest to largest
→If $\hat i$ denotes a unit vector along incident light ray, $\hat r$ a unit vector along refracted ray into a medium of refractive index $\mu $ and $\hat n$ unit vector normal to boundary of medium directed towards incident medium, then law of refraction is
→An image of the sun is formed by a lens of focal length of $30 cm$ on the metal surface of a photoelectric cell and a photoelectric current $I$ is produced. The lens forming the image is then replaced by another of the same diameter but of focal length $15 cm$. The photoelectric current in this case is
→If $|\,\vec A + \vec B\,|\, = \,|\,\vec A\,| + |\,\vec B\,|$, then angle between $\vec A$ and $\vec B$ will be ....... $^o$
→When a gas in a closed vessel was heated so as to increase its temperature by ${5^o}C$, there occurred an increase of $1\%$ in its pressure. The original temperature of the gas was ...... $^oC$
→The compressibility of water is $4 \times {10^{ - 5}}$ per unit atmospheric pressure. The decrease in volume of $100$ cubic centimeter of water under a pressure of $100$ atmosphere will be ......... $cc$
→A projectile is thrown with speed $40 \,ms ^{-1}$ at angle $\theta$ from horizontal. It is found that projectile is at same height at $1 \,s$ and $3 \,s$. What is the angle of projection?
→