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1. units,dimensions and measurement — Physics STD 11 Science — Question

Rajasthan BoardEnglish MediumSTD 11 SciencePhysics1. units,dimensions and measurement1 Mark
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.

$1 \text { Barn }=10^{-28}\, m ^2$

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