One person standing 10 m from a radiation source absorbs 1000 particles. A second person is standing 30 m from the same source, how many particles does the second person absorb? Assume that there is no difference in shielding between the two people.

Question

Quizplus · Accepted Answer

The intensity of radiation follows the inverse square law, meaning it decreases with the square of the distance. If the first person absorbs 1000 particles at 10 m, the second person at 30 m (which is 3 times farther) would absorb 1/9 of the particles, because (1/3)^2 = 1/9. Therefore, 1000 particles / 9 = 111 particles.

One Person Standing 10 M from a Radiation Source Absorbs