Test: Light - UPSC MCQ

The speed of light in a vacuum is approximately 300,000 kilometers per second (km/s).

Refraction is the phenomenon of light bending as it passes through a medium with a different refractive index.

A convex lens is thicker at the center than at the edges and causes light to converge (focus).

In the visible light spectrum, blue light has the highest frequency among the options you provided. The order of increasing frequency in the visible light spectrum is generally: red, orange, yellow, green, blue, indigo, and violet. Therefore, blue light has a higher frequency than red, green, and yellow light.

When white light passes through a prism, it splits into different colors, which is known as dispersion.

The bending of light as it passes around the edges of an obstacle or through an opening is called diffraction.

Convex mirrors are widely used for making magnifying glasses. In order to make a magnifying glass, two convex mirrors are placed back to back.

The distance between a lens and its focal point is called the focal length.

A green object reflects and transmits green light, while it absorbs other colors.

When light rays strike a rough surface, they undergo reflection in random directions.

The splitting of light into its constituent colors is observed in a rainbow.

Glass is the material that is most transparent to visible light.

Convex mirrors are used in rear view mirrors of motor vehicles. This is because they give an erect, virtual, full size diminished image of distant objects with a wider field of view.

Radioactivity is not a property of light. Reflection, diffraction, and interference are properties of light.

When light passes from a denser medium to a rarer medium, it speeds up.

Red light has the longest wavelength among the given options.

A convex lens is used to correct farsightedness.

The angle of incidence is equal to the angle of reflection according to the law of reflection.

The unit of luminous intensity is candela (cd).

A mirror is not a source of light. The Sun, Moon, and firefly are natural sources of light.