Question

Why are alpha rays much more dangerous when the source of radiation is located inside the body?

a. Alpha rays are less dangerous when outside the body because they are deactivated by light and air. However, once inside the body they can do great harm to any cells they come in contact with.

b. Alpha rays are less dangerous when outside the body because they are too far from blood cells. Inside the body they can do great harm if they can contact blood cells only.

c. Alpha rays are less dangerous when outside the body because they cannot penetrate the skin. However, once inside the body they can do great harm to any cells they come in contact with.

Answer 1

There are three type of ionizing radiation, namely alpha, beta and gamma out of which alpha is the least dangerous in terms of extenal exposure because it is least energetic waves out of the three, so it can't penetrate the skin. But once inhaled, injected or swallowed, then these rays are the most dangerous comparing to beta and gamma rays because they can do great harm to any cell they comes in contact with due to its high ionisation power.

Therefore, option C is the correct choice.