The Human Eye andthe Colourful World

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) Cornea
What part of the eye controls the size of the pupil?
a) Retina
b) Cornea
c) Iris
d) Optic nerve
Answer: c) Iris
Where is the image formed in the human eye?
a) Cornea
b) Iris
c) Retina
d) Pupil
Answer: c) Retina
The ability of the eye lens to adjust its focal length is called:
a) Refraction
b) Accommodation
c) Dispersion
d) Reflection
Answer: b) Accommodation
What 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 cm
What is the far point of a normal human eye?
a) 25 cm
b) Infinity
c) 1 m
d) 2 m
Answer: b) Infinity
What condition is caused when the crystalline lens becomes cloudy with age?
a) Myopia
b) Hypermetropia
c) Cataract
d) Astigmatism
Answer: c) Cataract
What is myopia also known as?
a) Near-sightedness
b) Far-sightedness
c) Astigmatism
d) Presbyopia
Answer: a) Near-sightedness
What 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 lens
In 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 retina
What is hypermetropia also known as?
a) Near-sightedness
b) Far-sightedness
c) Cataract
d) Astigmatism
Answer: b) Far-sightedness
What 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 lens
In 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 retina
What 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 lens
Which lens is used to correct presbyopia?
a) Concave lens
b) Convex lens
c) Bifocal lens
d) Cylindrical lens
Answer: c) Bifocal lens
What is the phenomenon of splitting white light into its component colors called?
a) Dispersion
b) Refraction
c) Reflection
d) Diffraction
Answer: a) Dispersion
The band of colors obtained when white light is dispersed is called:
a) Spectrum
b) Prism
c) Rainbow
d) Scattering
Answer: a) Spectrum
Who 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 Newton
What is the sequence of colors in the spectrum of white light?
a) ROYGBIV
b) VIBGYOR
c) BIVGYOR
d) YORGBIV
Answer: b) VIBGYOR
Which color of light bends the least in a prism?
a) Red
b) Violet
c) Blue
d) Green
Answer: a) Red
Why 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 molecules
Why 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 wavelengths
The phenomenon responsible for the twinkling of stars is:
a) Reflection
b) Atmospheric refraction
c) Dispersion
d) Diffraction
Answer: b) Atmospheric refraction
Why 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 light
What 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 prism
What 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 deviation
Which 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 reflection
A 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 Sun
What 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 cm
The 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 point
What 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) Presbyopia
Which 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 lens
What 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 lens
The twinkling of stars occurs due to:
a) Dispersion of light
b) Scattering of light
c) Atmospheric refraction
d) Internal reflection
Answer: c) Atmospheric refraction
Why 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 scattered
In what medium is the scattering of light minimum?
a) Vacuum
b) Air
c) Water
d) Glass
Answer: a) Vacuum
The 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 wavelengths
The 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 least
What 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 density
Why 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 atmosphere
What phenomenon explains why the apparent position of stars differs from their actual position?
a) Reflection
b) Refraction
c) Dispersion
d) Diffraction
Answer: b) Refraction
What is the cause of the apparent flattening of the Sun at sunrise and sunset?
a) Dispersion
b) Diffraction
c) Refraction
d) Reflection
Answer: c) Refraction
Which color in the spectrum of white light has the shortest wavelength?
a) Red
b) Green
c) Violet
d) Yellow
Answer: c) Violet
What type of lens is used to correct astigmatism?
a) Convex lens
b) Concave lens
c) Cylindrical lens
d) Plane lens
Answer: c) Cylindrical lens
Why 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 light
What 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 particles
What 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 clearly
The light-sensitive cells in the retina are called:
a) Cornea
b) Cones and rods
c) Iris
d) Optic nerves
Answer: b) Cones and rods
What 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 lens
What part of the eye carries electrical signals to the brain?
a) Retina
b) Iris
c) Optic nerve
d) Pupil
Answer: c) Optic nerve
What 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 cells
What 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) Cones
What 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 decreases
What 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) Presbyopia
Which component of the eye is responsible for controlling the amount of light entering?
a) Retina
b) Cornea
c) Iris
d) Optic nerve
Answer: c) Iris
What 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 lens
What is the phenomenon of light bending when it enters a medium of different density?
a) Reflection
b) Refraction
c) Dispersion
d) Diffraction
Answer: b) Refraction
What is the near point for a normal eye?
a) 25 cm
b) 2.5 m
c) 1 m
d) Infinity
Answer: a) 25 cm
What phenomenon makes the bottom of a swimming pool appear raised?
a) Reflection
b) Refraction
c) Diffraction
d) Scattering
Answer: b) Refraction
Which part of the eye is comparable to the aperture of a camera?
a) Iris
b) Cornea
c) Retina
d) Lens
Answer: a) Iris
What 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 brain
Why 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 atmosphere
Which color in the visible spectrum bends the most when passing through a prism?
a) Red
b) Yellow
c) Violet
d) Blue
Answer: c) Violet
What causes the splitting of light into its component colors?
a) Diffraction
b) Reflection
c) Dispersion
d) Scattering
Answer: c) Dispersion
What 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 inverted
Which light phenomenon explains the blue color of the sky?
a) Dispersion
b) Scattering
c) Refraction
d) Reflection
Answer: b) Scattering
The 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 scattered
Why 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 light
What 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 m
Why 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 angles
What 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 lens
What 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 particles
What 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 normal
What is the spectrum of sunlight also called?
a) Infrared spectrum
b) Ultraviolet spectrum
c) Continuous spectrum
d) Visible spectrum
Answer: d) Visible spectrum
Why 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 light
Which part of the eye helps in focusing light on the retina?
a) Iris
b) Cornea
c) Lens
d) Optic nerve
Answer: c) Lens
What is the term for the phenomenon where the Sun appears flattened at sunset?
a) Reflection
b) Refraction
c) Scattering
d) Diffraction
Answer: b) Refraction
Which color is scattered the least by the atmosphere?
a) Violet
b) Blue
c) Green
d) Red
Answer: d) Red
What type of lens is used for correcting myopia?
a) Concave lens
b) Convex lens
c) Cylindrical lens
d) Plane lens
Answer: a) Concave lens
What 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 diminished
Which part of the eye adjusts its curvature to focus on objects?
a) Retina
b) Ciliary muscles
c) Iris
d) Optic nerve
Answer: b) Ciliary muscles
What 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 smaller
What 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 atmosphere
What is the speed of light in a vacuum?
a) $\times 10^5 \, \text{m/s}$
b) $\times 10^8 \, \text{m/s}$
c) $\times 10^7 \, \text{m/s}$
d) $\times 10^6 \, \text{m/s}$
Answer: b) $\times 10^8 \, \text{m/s}$
What 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 angle
What 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 vision
What property of light causes a mirage in a desert?
a) Dispersion
b) Refraction
c) Scattering
d) Diffraction
Answer: b) Refraction
Which light phenomenon explains the bright streak of sunlight through a dense forest?
a) Dispersion
b) Tyndall effect
c) Diffraction
d) Refraction
Answer: b) Tyndall effect
The splitting of white light into seven colors is called:
a) Refraction
b) Scattering
c) Dispersion
d) Diffraction
Answer: c) Dispersion
Why 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 wavelengths
What 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 rays
What is the visual disorder caused by irregular curvature of the cornea?
a) Myopia
b) Hypermetropia
c) Astigmatism
d) Cataract
Answer: c) Astigmatism
What 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 size
What color is at the end of the visible spectrum with the longest wavelength?
a) Blue
b) Green
c) Red
d) Violet
Answer: c) Red
What is the primary component of the human eye that focuses light?
a) Iris
b) Cornea
c) Lens
d) Retina
Answer: c) Lens
What 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 wavelengths
What 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 eye
Which lens converges light rays?
a) Concave lens
b) Convex lens
c) Cylindrical lens
d) Plane lens
Answer: b) Convex lens
What 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 light
Why 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