Physics
Explain the following:
The sun is seen before the sunrise and after the sunset.
Answer
The upper atmospheric layers are warmer than the layers near the surface of the earth before sunrise and after sunset, so the layers near the earth's surface are more denser than upper layers. When sun is below horizon the rays of sun passes from rarer to denser medium and suffers refraction by bending towards the normal. Due to continuous bending of light rays the sun appears to be above horizon. So the sun is seen before the sunrise and after the sunset.
Related Questions
Explain the following:
A coin placed at the bottom of a vessel appears to be raised when water is poured in the vessel.
What is a prism? Draw a ray diagram to show the refraction of a light ray through a prism.
Explain the following:
A straight stick partly dipped in water obliquely, appears to be bent at the surface of water.
What is a mirage? Give a reason for its formation.