Question

Assertion : $\beta -particles$ have greater penetrating power than $\alpha -rays$ but less than $\gamma -rays$.
Reason : $\beta -particles$ are lighter than $\alpha -rays$ but heavier than $\gamma$.

• A. If both (A) and (R) are correct, and (R) is the correct explanation of (A).
• B. If both (A) and (R) are correct, but (R) is not the correct explanation of (A).
• C. If (A) is correct, but (R) is incorrect.
• D. If (A) is incorrect, but (R) is correct.
• E. If both (A) and (R) are incorrect.

Answer 1

The correct option is A If both (A) and (R) are correct, and (R) is the correct explanation of (A).

Gamma rays are the most penetrating of the radiations. Gamma rays are highly energetic waves.

Beta particles travel faster than alpha particles and carry less charge (one electron compared to the 2 protons of an alpha particle) and so interact less readily with the atoms and molecules of the material through which they pass.