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Nuclei — Physics STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 SciencePhysicsNuclei1 Mark
Question
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.
  1. Both A and R are true, and R is the correct explanation of A.
  2. Both A and R are true, but R is NOT the correct explanation of A.
  3. A is true, but R is false.
  4. A is false and R is also false.
Assertion (A): The nuclear force becomes weak if the nucleus contains too many protons compared to neutrons.
Reason (R): The electrostatic forces weaken the nuclear force.
✓

Answer

  1. A is true, but R is false.
Explanation:
Nuclear forces are strongest when the number of protons equals the number of neutrons. An excess of protons compared to neutrons weakens the nuclear force. Also, too many neutrons compared to protons inside the nucleus weaken the nuclear forces. The electrostatic force which is a hundred times less than the nuclear force is not the cause.

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