Question

A prismatic periscope is preferred to reflecting periscope because:

Options

• image formed by prismatic periscope is sharper than reflecting periscope.

• no rays of light are absorbed by prismatic periscope, but reflecting periscope absorbs some amount of light.

• deposition of dust or moisture does not affect prismatic periscope, but reduces visibility in case of reflecting periscope.

• all of these

Answer 1

All of these

Explanation:

A prism forms a sharper image because it reflects light by total internal reflection, with almost no light absorbed. Its reflecting surface is inside the prism, so dust and moisture do not reduce visibility as they can with a mirror.