Question

The occurrence of day and night suggests that

• A. Earth is flat
• B. Sun's shadow falls on the earth
• C. Rectilinear propagation of light
• D. Earth rotates around itself and Sun.

Answer 1

Answer: (C), (D)

The correct options are
C

Rectilinear propagation of light

D

Earth rotates around itself and Sun.

The light traveling in a straight line is called rectilinear propagation of light. If this were not so, then the light would have curved around the earth and there would have been sunlight around the earth. Earth is round in its shape and rotates around itself and the sun. While rotating half of its part is illuminated by sunlight and the other half is dark.