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 open tank filled with water (depsity $\rho$ ) has a narrow hole at a depth of h below the water surface. The velocity of water flowing out is
→A particle is moving in a circular path. The acceleration and momentum of the particle at a certain moment are $\vec a = (4\hat i + 3\hat j)\ m/s^2$ and $\vec p = (8\hat i - 6\hat j)\ kg-m/s$ . The motion of the particle is
→Given that a force $\vec F$ acts on a body for time $t_1$ and displaces the body by $\vec d$ . In which of the following cases the velocity of the body must increase?
→A body dropped from height $‘H’$ reaches the ground with a speed of $1.1 \sqrt {gH}$ . Calculate the work done by air friction? .............. $\mathrm{mgH}$
→An increases in pressure required to decreases the $200\,litres$ volume of a liquid by $0.004\%$ in container is ............ $kPa$ (Bulk modulus of the liquid $= 2100\,MPa$ )
→$A$ solid cone hangs from $a$ frictionless pivot at the origin $O$, as shown. If $\hat i$ , $\hat j$ and $\hat k$ are unit vectors, and $a, b$, and $c$ are positive constants, which of the following forces $F$ applied to the rim of the cone at a point $P$ results in a torque $\tau$ on the cone with a negative component $\tau_Z$
→The acceleration of a moving object can be determined by:
Young's modulus is determined by the equation given by $\mathrm{Y}=49000 \frac{\mathrm{m}}{\ell} \frac{\text { dyne }}{\mathrm{cm}^2}$ where $\mathrm{M}$ is the mass and $\ell$ is the extension of wre used in the experiment. Now error in Young modules $(\mathrm{Y})$ is estimated by taking data from $M-\ell$ plot in graph paper. The smallest scale divisions are $5 \mathrm{~g}$ and $0.02$ $\mathrm{cm}$ along load axis and extension axis respectively. If the value of $M$ and $\ell$ are $500 \mathrm{~g}$ and $2 \mathrm{~cm}$ respectively then percentage error of $\mathrm{Y}$ is :
→Two forces of $10 \,N$ and $6 \,N$ act upon a body. The direction of the forces are unknown. The resultant force on the body may be .........$N$
→Water is filled in a cylindrical container to a height of $3m. $ The ratio of the cross-sectional area of the orifice and the beaker is $ 0.1. $ The square of the speed of the liquid coming out from the orifice is ....... $m^2/s^2$ ($g = 10 m/s^2$)
→