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Nuclei — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsNuclei1 Mark
MCQ
For question, statements are given-one labelled Assertion $(A)$ and the other labelled Reason $(R).$ Select the correct answer to these questions from the codes $(a) (b) (c)$ and $(d)$ as given below.
Assertion $(A):$ Two protons can attract each other.
Reason $(R):$ The distance between the protons within the nucleus is about $10^{-15}m$
  • ✓
    Both $A$ and $R$ are true, and $R$ is the correct explanation of $A$.
  • B
    Both $A$ and $R$ are true, but $R$ is not the correct explanation of $A$.
  • C
    $A$ is true, but $R$ is false.
  • D
    $A$ is false and $R$ is also false.
✓

Answer

Correct option: A.
Both $A$ and $R$ are true, and $R$ is the correct explanation of $A$.
Due to electrostatic forces between two protons $($like charges$)$ there is a force of repulsion. However, when the distance between them is $~ 10-15m$ they come under the influence of the short range, strong nuclear forces. $($The range of the nuclear forces is $~ 10^{-15}m).$ These forces are attractive forces and charges independent. The net force on the protons is attractive, as nuclear forces are much stronger than electrostatic forces. The protons attract each other.

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