Which term refers to the very darkest part of the moon's shadow, where the light source is not visible?

Which term refers to the very darkest part of the moon's shadow, where the light source is not visible?

• A. Penumbra
• B. Umbra
• C. Cohesion
• D. Transpiration

Answer: (B)

In a lunar eclipse, the darkest part of the Moon’s shadow is where the light source is completely blocked and not visible. This region is called the umbra. Outside of it lies the penumbra, where part of the Sun still shines and the shadow is lighter. The other terms—cohesion and transpiration—aren’t related to shadows: cohesion is about how molecules attract each other, and transpiration is how plants lose water. So the darkest part of the Moon’s shadow is the umbra.

In a lunar eclipse, the darkest part of the Moon’s shadow is where the light source is completely blocked and not visible. This region is called the umbra. Outside of it lies the penumbra, where part of the Sun still shines and the shadow is lighter. The other terms—cohesion and transpiration—aren’t related to shadows: cohesion is about how molecules attract each other, and transpiration is how plants lose water. So the darkest part of the Moon’s shadow is the umbra.