Question

Assertion (A): The source of $\alpha$- particles are taken in a lead block.

Reason (R): Some radioactive emanations can penetrate through lead block.

• A. 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 and R is false.
• D. A is false and R is true.

Answer 1

The correct option is A

Both A and R are true and R is the correct explanation of A.

The explanation for the correct option:

The explanation for the Assertion statement:

1. Lead has a high density and particles cannot pass through it, it was utilized to keep the source in the ray scattering experiment.
2. As a result, in this experiment, a lead plate box of adequate thickness is used.
3. Thus, Assertion (A) is true.

The explanation for the Reason statement:

1. In the Lead box, the radioactive chemical utilized in the experiment is maintained.
2. Alpha, beta particles cannot penetrate lead because of their high density (lead).
3. This aids in concentrating the particle beam towards the gold foil. Also, if these particles infiltrate the body, they may disrupt DNA, contributing to the carcinogenic effect.
4. Thus, Reason (R) is true and is the correct explanation of A.

The correct option is A) Both A and R are true and R is the correct explanation of A.