Which statement best describes the edge of a shadow near the object producing it?

Which statement best describes the edge of a shadow near the object producing it?

• A. The Edge Near the Object Is Sharper
• B. The Edge Near the Object Is Softer
• C. Edges Are Equally Sharp
• D. Edges Are Irrelevant

Answer: (A)

The edge of a shadow is sharpened by the way light comes from the source. When the light source is extended (not a single point), the shadow has an inner area (umbra) where the object completely blocks all light, producing a relatively crisp boundary. Right at the edge closer to the object, the lines of sight to the light source are blocked more completely, so the transition from light to shadow is abrupt. As you move away from the object, more of the light source starts to peek around the edges, creating a gradual transition called the penumbra, which makes the boundary softer. So the edge near the object is the sharper one.

The edge of a shadow is sharpened by the way light comes from the source. When the light source is extended (not a single point), the shadow has an inner area (umbra) where the object completely blocks all light, producing a relatively crisp boundary. Right at the edge closer to the object, the lines of sight to the light source are blocked more completely, so the transition from light to shadow is abrupt. As you move away from the object, more of the light source starts to peek around the edges, creating a gradual transition called the penumbra, which makes the boundary softer. So the edge near the object is the sharper one.