Whether a concave lens is called a converging or diverging lens? Answer with reason.

A ray parallel to the principal axis of a concave mirror follows which path after reflection by the concave mirror?

Write one use of a convex mirror

In the case of refraction of white light through a prism, the light of colour which deviates the least is yellow orange red violet

What is meant by the principal axis of a concave lens?

Determine the angle of deviation for the refraction of light rays from rarer to denser medium. [2] (angle of incidence = i, angle of refraction = r) OR Why do the green leaves of trees appear 'green' in sunlight? [2]

Why is the red colour selected for danger signal lights?

Determine the speed of a light ray passing through a glass slab of refractive index 1.5. [c = 3 × 10⁵ m s⁻¹]

Explain with a suitable ray diagram the process of formation of image by a concave lens.

Explain with a diagram why the sky appears blue.

Define dispersion of light. How would you identify monochromatic light and composite light with the help of a prism? [1 + 2]

Write down the relationship between relative refractive index and absolute refractive index. On which factors does the relative refractive index of a medium depend? [1 + 2] OR Show that if a monochromatic light ray passes symmetrically through an equilateral prism then the angle of deviation of that ray will be minimum