
The Human Eye and the Colorful World
What is the transparent bulge on the front surface of the eyeball called?
a) Cornea
b) Retina
c) Iris
d) Pupil
Answer: a) CorneaWhat part of the eye controls the size of the pupil?
a) Retina
b) Cornea
c) Iris
d) Optic nerve
Answer: c) IrisWhere is the image formed in the human eye?
a) Cornea
b) Iris
c) Retina
d) Pupil
Answer: c) RetinaThe ability of the eye lens to adjust its focal length is called:
a) Refraction
b) Accommodation
c) Dispersion
d) Reflection
Answer: b) AccommodationWhat is the least distance of distinct vision for a normal eye?
a) 50 cm
b) 25 cm
c) 1 m
d) 15 cm
Answer: b) 25 cmWhat is the far point of a normal human eye?
a) 25 cm
b) Infinity
c) 1 m
d) 2 m
Answer: b) InfinityWhat condition is caused when the crystalline lens becomes cloudy with age?
a) Myopia
b) Hypermetropia
c) Cataract
d) Astigmatism
Answer: c) CataractWhat is myopia also known as?
a) Near-sightedness
b) Far-sightedness
c) Astigmatism
d) Presbyopia
Answer: a) Near-sightednessWhat type of lens is used to correct myopia?
a) Convex lens
b) Concave lens
c) Cylindrical lens
d) None of the above
Answer: b) Concave lensIn myopia, the image is formed:
a) On the retina
b) Behind the retina
c) In front of the retina
d) None of the above
Answer: c) In front of the retinaWhat is hypermetropia also known as?
a) Near-sightedness
b) Far-sightedness
c) Cataract
d) Astigmatism
Answer: b) Far-sightednessWhat type of lens is used to correct hypermetropia?
a) Convex lens
b) Concave lens
c) Cylindrical lens
d) None of the above
Answer: a) Convex lensIn hypermetropia, the image is formed:
a) On the retina
b) Behind the retina
c) In front of the retina
d) None of the above
Answer: b) Behind the retinaWhat causes presbyopia?
a) Increased flexibility of the eye lens
b) Decreased flexibility of the eye lens
c) Elongation of the eyeball
d) Excessive curvature of the eye lens
Answer: b) Decreased flexibility of the eye lensWhich lens is used to correct presbyopia?
a) Concave lens
b) Convex lens
c) Bifocal lens
d) Cylindrical lens
Answer: c) Bifocal lensWhat is the phenomenon of splitting white light into its component colors called?
a) Dispersion
b) Refraction
c) Reflection
d) Diffraction
Answer: a) DispersionThe band of colors obtained when white light is dispersed is called:
a) Spectrum
b) Prism
c) Rainbow
d) Scattering
Answer: a) SpectrumWho was the first to demonstrate the dispersion of light using a prism?
a) Isaac Newton
b) Albert Einstein
c) Galileo Galilei
d) James Clerk Maxwell
Answer: a) Isaac NewtonWhat is the sequence of colors in the spectrum of white light?
a) ROYGBIV
b) VIBGYOR
c) BIVGYOR
d) YORGBIV
Answer: b) VIBGYORWhich color of light bends the least in a prism?
a) Red
b) Violet
c) Blue
d) Green
Answer: a) RedWhy does the sky appear blue?
a) Reflection of light
b) Refraction of light
c) Scattering of blue light by air molecules
d) Dispersion of light
Answer: c) Scattering of blue light by air moleculesWhy does the sun appear reddish at sunrise and sunset?
a) Dispersion of light
b) Scattering of red light due to longer wavelengths
c) Refraction of red light
d) Reflection of red light
Answer: b) Scattering of red light due to longer wavelengthsThe phenomenon responsible for the twinkling of stars is:
a) Reflection
b) Atmospheric refraction
c) Dispersion
d) Diffraction
Answer: b) Atmospheric refractionWhy don’t planets twinkle like stars?
a) They are closer to Earth
b) They are point sources
c) They are extended sources of light
d) They don’t undergo atmospheric refraction
Answer: c) They are extended sources of lightWhat is the angle between the refracting surfaces of a prism called?
a) Angle of incidence
b) Angle of deviation
c) Angle of refraction
d) Angle of the prism
Answer: d) Angle of the prismWhat is the angle between the incident ray and the emergent ray in a prism called?
a) Angle of incidence
b) Angle of deviation
c) Angle of emergence
d) Angle of refraction
Answer: b) Angle of deviationWhich phenomenon is responsible for the formation of a rainbow?
a) Dispersion and refraction
b) Reflection and refraction
c) Dispersion, refraction, and internal reflection
d) Reflection and scattering
Answer: c) Dispersion, refraction, and internal reflectionA rainbow is always formed in the direction:
a) Opposite to the Sun
b) Towards the Sun
c) Perpendicular to the Sun
d) Parallel to the ground
Answer: a) Opposite to the SunWhat is the minimum distance at which the human eye can see objects clearly without strain?
a) 10 cm
b) 25 cm
c) 1 m
d) 50 cm
Answer: b) 25 cmThe farthest point up to which the human eye can see clearly is called:
a) Near point
b) Far point
c) Focal length
d) Visual range
Answer: b) Far pointWhat is the condition where a person suffers from both myopia and hypermetropia?
a) Cataract
b) Presbyopia
c) Astigmatism
d) None of the above
Answer: b) PresbyopiaWhich of the following lenses is used in bifocal glasses for distant vision?
a) Concave lens
b) Convex lens
c) Cylindrical lens
d) Plane lens
Answer: a) Concave lensWhat type of lens is used for reading in bifocal glasses?
a) Concave lens
b) Convex lens
c) Cylindrical lens
d) Plane lens
Answer: b) Convex lensThe twinkling of stars occurs due to:
a) Dispersion of light
b) Scattering of light
c) Atmospheric refraction
d) Internal reflection
Answer: c) Atmospheric refractionWhy is the danger signal red in color?
a) Red is least scattered
b) Red is the brightest color
c) Red has the shortest wavelength
d) Red is absorbed by particles
Answer: a) Red is least scatteredIn what medium is the scattering of light minimum?
a) Vacuum
b) Air
c) Water
d) Glass
Answer: a) VacuumThe color of the sky on a clear day is blue due to:
a) Refraction
b) Dispersion
c) Scattering of shorter wavelengths
d) Scattering of longer wavelengths
Answer: c) Scattering of shorter wavelengthsThe reddening of the sun at sunset occurs because:
a) The Sun emits red light at that time
b) Red light is scattered the least
c) Red light is scattered the most
d) Blue light is absorbed by the Sun
Answer: b) Red light is scattered the leastWhat is the primary cause of atmospheric refraction?
a) Variation in air density
b) Curvature of the Earth
c) Reflection by clouds
d) Presence of dust particles
Answer: a) Variation in air densityWhy is the Sun visible for a short time even after it sets?
a) Reflection of sunlight by the Moon
b) Refraction of sunlight by the atmosphere
c) Scattering of sunlight by dust particles
d) Dispersion of sunlight by water vapor
Answer: b) Refraction of sunlight by the atmosphereWhat phenomenon explains why the apparent position of stars differs from their actual position?
a) Reflection
b) Refraction
c) Dispersion
d) Diffraction
Answer: b) RefractionWhat is the cause of the apparent flattening of the Sun at sunrise and sunset?
a) Dispersion
b) Diffraction
c) Refraction
d) Reflection
Answer: c) RefractionWhich color in the spectrum of white light has the shortest wavelength?
a) Red
b) Green
c) Violet
d) Yellow
Answer: c) VioletWhat type of lens is used to correct astigmatism?
a) Convex lens
b) Concave lens
c) Cylindrical lens
d) Plane lens
Answer: c) Cylindrical lensWhy does the sky appear dark to astronauts in space?
a) No air to scatter light
b) Excessive scattering of light
c) No light in space
d) Light is absorbed by stars
Answer: a) No air to scatter lightWhat is the Tyndall effect?
a) Dispersion of white light
b) Scattering of light by colloidal particles
c) Reflection of light by surfaces
d) Refraction of light in water
Answer: b) Scattering of light by colloidal particlesWhat happens when the focal length of the eye lens increases?
a) Nearby objects are seen clearly
b) Distant objects are seen clearly
c) The eye cannot focus on any object
d) Vision becomes blurred
Answer: b) Distant objects are seen clearlyThe light-sensitive cells in the retina are called:
a) Cornea
b) Cones and rods
c) Iris
d) Optic nerves
Answer: b) Cones and rodsWhat is the function of the ciliary muscles in the eye?
a) Controlling the size of the pupil
b) Focusing the image on the retina
c) Changing the curvature of the lens
d) Adjusting the amount of light entering the eye
Answer: c) Changing the curvature of the lensWhat part of the eye carries electrical signals to the brain?
a) Retina
b) Iris
c) Optic nerve
d) Pupil
Answer: c) Optic nerveWhat is the primary function of the retina in the human eye?
a) Control the size of the pupil
b) Refract incoming light
c) Form images using light-sensitive cells
d) Provide nutrients to the cornea
Answer: c) Form images using light-sensitive cellsWhat is the term used for the light-sensitive cells responsible for color vision?
a) Rods
b) Cones
c) Optic nerves
d) Ciliary muscles
Answer: b) ConesWhat happens when the eye lens becomes thickened?
a) The focal length decreases
b) The focal length increases
c) The retina adjusts
d) The pupil enlarges
Answer: a) The focal length decreasesWhat condition occurs when the eye loses the ability to focus on nearby objects due to aging?
a) Myopia
b) Hypermetropia
c) Presbyopia
d) Astigmatism
Answer: c) PresbyopiaWhich component of the eye is responsible for controlling the amount of light entering?
a) Retina
b) Cornea
c) Iris
d) Optic nerve
Answer: c) IrisWhat is the primary cause of cataract in the eye?
a) Excessive refraction of light
b) Weakening of ciliary muscles
c) Clouding of the lens
d) Damage to the retina
Answer: c) Clouding of the lensWhat is the phenomenon of light bending when it enters a medium of different density?
a) Reflection
b) Refraction
c) Dispersion
d) Diffraction
Answer: b) RefractionWhat is the near point for a normal eye?
a) 25 cm
b) 2.5 m
c) 1 m
d) Infinity
Answer: a) 25 cmWhat phenomenon makes the bottom of a swimming pool appear raised?
a) Reflection
b) Refraction
c) Diffraction
d) Scattering
Answer: b) RefractionWhich part of the eye is comparable to the aperture of a camera?
a) Iris
b) Cornea
c) Retina
d) Lens
Answer: a) IrisWhat is the main role of the optic nerve?
a) Adjust the curvature of the lens
b) Transmit signals from the retina to the brain
c) Focus light on the retina
d) Control the size of the pupil
Answer: b) Transmit signals from the retina to the brainWhy is the Sun visible even after it has set?
a) Dispersion of sunlight
b) Reflection of sunlight
c) Refraction by the atmosphere
d) Scattering of sunlight
Answer: c) Refraction by the atmosphereWhich color in the visible spectrum bends the most when passing through a prism?
a) Red
b) Yellow
c) Violet
d) Blue
Answer: c) VioletWhat causes the splitting of light into its component colors?
a) Diffraction
b) Reflection
c) Dispersion
d) Scattering
Answer: c) DispersionWhat type of image is formed on the retina?
a) Virtual and upright
b) Real and inverted
c) Real and upright
d) Virtual and inverted
Answer: b) Real and invertedWhich light phenomenon explains the blue color of the sky?
a) Dispersion
b) Scattering
c) Refraction
d) Reflection
Answer: b) ScatteringThe red light in traffic signals is used because it:
a) Travels the fastest
b) Is least scattered
c) Is more attractive
d) Is reflected the most
Answer: b) Is least scatteredWhy do astronauts see a dark sky instead of a blue one?
a) Absence of sunlight
b) Lack of atmosphere to scatter light
c) Absorption of light in space
d) Reflection of light by space particles
Answer: b) Lack of atmosphere to scatter lightWhat is the focal length of a convex lens of power +2D?
a) 2 m
b) 1 m
c) 0.5 m
d) 5 m
Answer: c) 0.5 mWhy does a prism create a spectrum?
a) Refraction and reflection
b) Reflection and diffraction
c) Different wavelengths refract by different angles
d) Absorption of specific colors
Answer: c) Different wavelengths refract by different anglesWhat does the term “accommodation of the eye” refer to?
a) Adjustment of pupil size
b) Adjustment of the focal length of the lens
c) Adjustment of retina sensitivity
d) Adjustment of iris curvature
Answer: b) Adjustment of the focal length of the lensWhat is the Tyndall effect caused by?
a) Reflection of light
b) Scattering of light by particles
c) Refraction of light through water
d) Absorption of light by air
Answer: b) Scattering of light by particlesWhat happens to light when it passes from air into water?
a) It speeds up
b) It bends away from the normal
c) It slows down and bends towards the normal
d) It reflects completely
Answer: c) It slows down and bends towards the normalWhat is the spectrum of sunlight also called?
a) Infrared spectrum
b) Ultraviolet spectrum
c) Continuous spectrum
d) Visible spectrum
Answer: d) Visible spectrumWhy do planets not twinkle?
a) They are very close to Earth
b) They emit their own light
c) They are extended sources of light
d) They do not undergo atmospheric refraction
Answer: c) They are extended sources of lightWhich part of the eye helps in focusing light on the retina?
a) Iris
b) Cornea
c) Lens
d) Optic nerve
Answer: c) LensWhat is the term for the phenomenon where the Sun appears flattened at sunset?
a) Reflection
b) Refraction
c) Scattering
d) Diffraction
Answer: b) RefractionWhich color is scattered the least by the atmosphere?
a) Violet
b) Blue
c) Green
d) Red
Answer: d) RedWhat type of lens is used for correcting myopia?
a) Concave lens
b) Convex lens
c) Cylindrical lens
d) Plane lens
Answer: a) Concave lensWhat is the nature of an image formed by a concave lens?
a) Virtual, erect, and magnified
b) Virtual, erect, and diminished
c) Real, inverted, and magnified
d) Real, inverted, and diminished
Answer: b) Virtual, erect, and diminishedWhich part of the eye adjusts its curvature to focus on objects?
a) Retina
b) Ciliary muscles
c) Iris
d) Optic nerve
Answer: b) Ciliary musclesWhat happens to the pupil size in bright light?
a) It becomes smaller
b) It becomes larger
c) It remains the same
d) It disappears
Answer: a) It becomes smallerWhat is the main reason for the advanced sunrise?
a) Dispersion of sunlight
b) Refraction of sunlight by the atmosphere
c) Scattering of sunlight
d) Reflection by clouds
Answer: b) Refraction of sunlight by the atmosphereWhat is the speed of light in a vacuum?
a) 3×105m/s
b) 3×108m/s
c) 3×107m/s
d) 3×106m/s
Answer: b) 3×108m/sWhat is the minimum angle of deviation for a prism called?
a) Critical angle
b) Dispersion angle
c) Minimum deviation angle
d) Refractive angle
Answer: c) Minimum deviation angleWhat does the term “least distance of distinct vision” mean?
a) Maximum distance of clear vision
b) Closest distance for clear vision
c) Distance between lens and retina
d) Closest distance for blurred vision
Answer: b) Closest distance for clear visionWhat property of light causes a mirage in a desert?
a) Dispersion
b) Refraction
c) Scattering
d) Diffraction
Answer: b) RefractionWhich light phenomenon explains the bright streak of sunlight through a dense forest?
a) Dispersion
b) Tyndall effect
c) Diffraction
d) Refraction
Answer: b) Tyndall effectThe splitting of white light into seven colors is called:
a) Refraction
b) Scattering
c) Dispersion
d) Diffraction
Answer: c) DispersionWhy do different colors bend at different angles in a prism?
a) Different wavelengths
b) Different speeds in a vacuum
c) Same wavelength but different refraction indices
d) Reflection inside the prism
Answer: a) Different wavelengthsWhat is the role of the cornea in the eye?
a) Focuses light rays
b) Controls the pupil size
c) Sends signals to the brain
d) Protects the iris
Answer: a) Focuses light raysWhat is the visual disorder caused by irregular curvature of the cornea?
a) Myopia
b) Hypermetropia
c) Astigmatism
d) Cataract
Answer: c) AstigmatismWhat type of image is formed by a plane mirror?
a) Real, inverted, and same size
b) Virtual, erect, and same size
c) Real, erect, and enlarged
d) Virtual, inverted, and diminished
Answer: b) Virtual, erect, and same sizeWhat color is at the end of the visible spectrum with the longest wavelength?
a) Blue
b) Green
c) Red
d) Violet
Answer: c) RedWhat is the primary component of the human eye that focuses light?
a) Iris
b) Cornea
c) Lens
d) Retina
Answer: c) LensWhat phenomenon makes the Sun appear reddish at sunrise and sunset?
a) Dispersion
b) Scattering of shorter wavelengths
c) Scattering of longer wavelengths
d) Refraction
Answer: c) Scattering of longer wavelengthsWhat happens when the pupil dilates?
a) More light enters the eye
b) Less light enters the eye
c) The lens becomes thicker
d) The retina shrinks
Answer: a) More light enters the eyeWhich lens converges light rays?
a) Concave lens
b) Convex lens
c) Cylindrical lens
d) Plane lens
Answer: b) Convex lensWhat determines the color of the sky?
a) Dispersion of light
b) Reflection of light
c) Scattering of light
d) Absorption of light
Answer: c) Scattering of lightWhy does white light split into colors when it passes through a prism?
a) Reflection of light inside the prism
b) Refraction and different wavelengths
c) Absorption of colors
d) Scattering by the prism’s edges
Answer: b) Refraction and different wavelengths