The Human Eye and Colourful World

A person cannot see distinctly objects kept beyond 2 m. This defect can be corrected by using a lens of power
1. + 0.5 D
2. – 0.5 D
3. + 0.2 D
4. – 0.2 D
The muscular diaphragm that controls the size of the pupil is
1. cornea
2. ciliary muscles
3. iris
4. retina
A student sitting on the last bench can read the letters written on the blackboard but is not able to read the letters written in his text book. Which of the following statements is correct?
1. The near point of his eyes has receded away
2. The near point of his eyes has come closer to him
3. The far point of his eyes has come closer to him
4. The far point of his eyes has receded away
Having two eyes facilitates in
A : Increasing the field of view
B : Bringing three-dimensional view
C : Developing the concept of distance/ size
Then the correct option is/are
1. A only
2. A and B only
3. B only
4. A, B and C
The black opening between the aqueous humour and the lens is called
1. retina
2. iris
3. cornea
4. pupil
At noon the sun appears white as
1. light is least scattered
2. all the colours of the white light are scattered away
3. blue colour is scattered the most
4. red colour is scattered the most
Which of the following phenomena of light are involved in the formation of a rainbow?
1. Reflection, refraction and dispersion
2. Refraction, dispersion and total internal reflection
3. Refraction, dispersion and internal reflection
4. Dispersion, scattering and total internal reflection
Near and far points of a young person normal eye respectively are
1. 0 and infinity
2. 0 and 25cm
3. 25 cm and infinity
4. 25 cm and 150cm
Twinkling of stars is due to atmospheric
1. dispersion of light by water droplets
2. refraction of light by different layers of varying refractive indices
3. scattering of light by dust particles
4. internal reflection of light by clouds
The defect of vision in which the person is able to see distant object distinctly but cannot see nearby objects clearly is called
1. Long-sightedness
2. Far-sightedness
3. Hypermetropia
4. all
The clear sky appears blue because
1. blue light gets absorbed in the atmosphere
2. ultraviolet radiations are absorbed in the atmosphere
3. violet and blue lights get scattered more than lights of all other colours by the atmosphere
4. light of all other colours is scattered more than the violet and blue colour lights by the atmosphere
Which of the following statements is correct regarding the propagation of light of different colours of white light in air?
1. Red light moves fastest
2. Blue light moves faster than green light
3. All the colours of the white light move with the same speed
4. Yellow light moves with the mean speed as that of the red and the violet light
The danger signals installed at the top of tall buildings are red in colour. These can be easily seen from a distance because among all other colours, the red light
1. is scattered the most by smoke or fog
2. is scattered the least by smoke or fog
3. is absorbed the most by smoke or fog
4. moves fastest in air
Which of the following phenomena contributes significantly to the reddish appearance of the sun at sunrise or sunset?
1. Dispersion of light
2. Scattering of light
3. Total internal reflection of light
4. Reflection of light from the earth
The bluish colour of water in deep sea is due to
1. the presence of algae and other plants found in water
2. reflection of sky in water
3. scattering of light
4. absorption of light by the sea
When light rays enter the eye, most of the refraction occurs at the
1. crystalline lens
2. outer surface of the cornea
3. iris
4. pupil
The focal length of the eye lens increases when eye muscles
1. are relaxed and lens becomes thinner
2. contract and lens becomes thicker
3. are relaxed and lens becomes thicker
4. contract and lens becomes thinner
Which of the following statement is correct?
1. A person with myopia can see distant objects clearly
2. A person with hypermetropia can see nearby objects clearly
3. A person with myopia can see nearby objects clearly
4. A person with hypermetropia cannot see distant objects clearly
The ability of eye lens to adjust its focal length to form a sharp image of the object at varying distances on the retina is called
1. Power of observation of the eye
2. Power of adjustment of the eye
3. Power of accommodation of the eye
4. Power of enabling of the eye
Myopia and hypermetropia can be corrected by
1. Concave and plano-convex lens
2. Concave and convex lens
3. Convex and concave lens
4. Plano-concave lens for both defects.
Bi-focal lens are required to correct
1. astigmatism
2. coma
3. myopia
4. presbyopia
The image formed on the retina of the human eye is
1. virtual and inverted
2. real and inverted
3. real and erect
4. virtual and erect

The Human Eye and Colourful World

Quiz