The Human Eye and the Colourful World Quiz

What is the function of the lens in the human eye?

• To focus light on the retina

• To control the size of the pupil

• To refract light away from the cornea

• To generate electrical signals

What is the near point of the normal human eye?

• 10 cm

• 25 cm

• 50 cm

• 1 m

Which muscle controls the curvature of the eye lens?

• Iris

• Ciliary muscles

• Cornea

• Optic nerve

A person who can see nearby objects clearly but not distant objects has which defect?

• Myopia

• Hypermetropia

• Presbyopia

• Astigmatism

What type of lens corrects myopia?

• Concave lens

• Convex lens

• Cylindrical lens

• Bifocal lens

The splitting of white light into its component colors is called?

• Reflection

• Refraction

• Dispersion

• Diffraction

Why does the sky appear blue?

• Because blue light is scattered more by atmosphere

• Because red light is absorbed

• Because blue light is reflected by clouds

• Because sunlight only contains blue light

Why do stars twinkle?

• Because of atmospheric refraction

• Because stars change brightness

• Because of pollution

• Because of the stars' rotation

Why don't planets twinkle like stars?

• Planets are closer and appear as extended sources

• Planets emit constant light

• Planetary atmospheres block twinkling

• Planets do twinkle

What causes a rainbow to form in the sky?

• Dispersion and internal reflection of sunlight in raindrops

• Reflection of sunlight by clouds

• Absorption of light by water droplets

• Refraction of light by snowflakes