Which statement describes the inverse square law?

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Multiple Choice

Which statement describes the inverse square law?

Explanation:
The inverse square law describes how dose diminishes as you move away from the radiation source, with intensity proportional to 1 divided by distance squared. In practical terms, when you double the distance, the exposure drops to one-quarter. For example, if the dose at 1 unit of distance is D, at 2 units of distance it becomes D/4; at half the distance, it would be four times as much. This is why distance is such a powerful protection factor in radiography—small increases in distance lead to large reductions in exposure. If you move farther away, you don’t just cut exposure in half; you cut it by a factor of four when you double the distance. The other statements don’t fit because dose does not increase with distance, does not stay the same regardless of distance, and does not double when distance doubles—the dose actually decreases with the square of the distance.

The inverse square law describes how dose diminishes as you move away from the radiation source, with intensity proportional to 1 divided by distance squared. In practical terms, when you double the distance, the exposure drops to one-quarter. For example, if the dose at 1 unit of distance is D, at 2 units of distance it becomes D/4; at half the distance, it would be four times as much.

This is why distance is such a powerful protection factor in radiography—small increases in distance lead to large reductions in exposure. If you move farther away, you don’t just cut exposure in half; you cut it by a factor of four when you double the distance.

The other statements don’t fit because dose does not increase with distance, does not stay the same regardless of distance, and does not double when distance doubles—the dose actually decreases with the square of the distance.

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