The light energy that hits a vertical surface is stronger than that hitting a slanted surface because it is ______ on a smaller area.

The light energy that hits a vertical surface is stronger than that hitting a slanted surface because it is ______ on a smaller area.

• A. diffused
• B. weaker
• C. spread out
• D. concentrated

Answer: (D)

The amount of light energy that arrives is the same, but how it is spread over a surface determines how strong it feels. A vertical surface that faces the light catches the beam in a smaller footprint, so the energy is confined to a smaller area. That means a higher energy per unit area, or a stronger effect. A slanted surface presents a larger footprint to the light, spreading the energy over a bigger area and reducing the intensity. So the best fit is that the energy on the vertical surface is concentrated on a smaller area.

The amount of light energy that arrives is the same, but how it is spread over a surface determines how strong it feels. A vertical surface that faces the light catches the beam in a smaller footprint, so the energy is confined to a smaller area. That means a higher energy per unit area, or a stronger effect. A slanted surface presents a larger footprint to the light, spreading the energy over a bigger area and reducing the intensity. So the best fit is that the energy on the vertical surface is concentrated on a smaller area.