Question

(a) A ray of light, passing from one medium to another, does not bend its path if its angle of incidence equals ____ degree.

a) 0
b) 45
c) 90
d) 180

(b) The phenomenon of the splitting of white light into seven colors is known as the phenomenon of _____.
a) Diffraction
b) Dispersion
c) Reflection
d) Refraction

(c) The point, on the principal axis of a concave lens, from where a beam of incident parallel ray appears to diverge, is called the _______ of the concave lens.
a) Focus
b) Vertex
c) Focal length
d) Principal focus

The more the optical density of a given medium, the _________ is the speed of light through it.
a) Slower
b) Faster
c) Unchanged
d) Variable

An object should be placed at the ______ point so that a convex lens forms its real and inverted image of the same size.
a) Focal
b) Vertex
c) Principal
d) Center

Answer 1

The angle of incidence that prevents a light ray from bending is 0 degrees. The splitting of white light into its spectrum is called dispersion. For a concave lens, the point of apparent divergence is the principal focus, and light travels slower through denser media. To get a real, inverted image of the same size using a convex lens, the object must be placed at the principal point.

Step-by-step explanation:

(a) A ray of light, passing from one medium to another, does not bend its path if its angle of incidence equals 0 degrees. Therefore, the correct answer is a) 0.

(b) The phenomenon of the splitting of white light into seven colors is known as the phenomenon of dispersion. So, the correct answer is b) Dispersion.

(c) The point, on the principal axis of a concave lens, from where a beam of incident parallel ray appears to diverge, is called the principal focus of the concave lens. Here the right answer is d) Principal focus.

The more the optical density of a given medium, the slower is the speed of light through it. Hence, the right option is a) Slower.

An object should be placed at the principal point so that a convex lens forms its real and inverted image of the same size. Thus, the correct answer is c) Principal.