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Q126. LIST (Visual Defects) List-II (Treatment) A. Near vision defects 1.Convex lens B. Far vision defects 2.Bifocal lens C. Zara vision defects 3.Cylindrical lens D. Non-concavity 4. Concave lens
- AABCD 1 2 3 4
- BABCD 1 4 3 2
- CABCD 4 3 2 1
- DABCD 4 1 2 3
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Answer: D) ABCD 4 1 2 3
Q127. Which one of the following is not correct about the image formed by a plane mirror?
- AIts shape is the same as that of the object used.
- BIt is laterally inverted (inverted/reversed)
- CThis is a real image
- DIt is formed at the same distance behind the mirror as the object is in front of the mirror.
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Answer: A) Its shape is the same as that of the object used.
Q128. Which of the following statements regarding lenses is not correct?
- AA convex lens forms both real and virtual images
- BA concave lens forms both real and virtual images
- Cconvex lens can form an image equal to the size of the object, larger than the object, and smaller than the object.
- DA concave lens always forms an image smaller than the size of the object
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Answer: B) A concave lens forms both real and virtual images
Q129. Used to cure farsightedness
- Aconcave lens
- Bconvex mirror
- Cconvex lens
- Dconcave mirror
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Answer: C) convex lens
Q130. What is meant by myopia?
- Afarsightedness
- Bnearsightedness
- Ccolor blindness
- Dnight blindness
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Answer: B) nearsightedness
Q131. Hypermetropia means-
- Anearsightedness
- Bfarsightedness
- Ca little far sight
- DPresbyopia
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Answer: B) farsightedness
Q132. man cannot see clearly objects more than 10 meters away. What defect of vision does he suffer from?
- AHypermetropia
- BHydrophobia
- Cmyopia
- DCataract
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Answer: C) myopia
Q133. A person cannot see clearly objects less than 1 meter away. What defect does that person suffer from?
- Along-sightedness
- Bnearsightedness
- CDisease of the rhythm
- DNone of these
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Answer: A) long-sightedness
Q134. Two plane mirrors are placed in a periscope-
- Aparallel to each other
- Bperpendicular to each other
- Cmaking an angle of 60° with each other
- Dmaking an angle of 45° with each other
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Answer: A) parallel to each other
Q135. What is a telescope?
- Adistant object is seen
- BNearby objects are seen
- CThe depth of water is measured
- Dnone of these
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Answer: A) distant object is seen
Q136. What does a watchmaker use to look at the fine parts of a watch?
- Aphoto camera
- Bmagnifying lens
- Ccompound microscope
- DVisionary
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Answer: B) magnifying lens
Q137. What is used in biology laboratories to view magnified images of microscopic cells or organisms?
- Aphoto camera
- BSimple microscope
- Ccompound microscope
- DVisionary
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Answer: C) compound microscope
Q138. Which optical instrument is used to observe distant objects?
- ASimple microscope
- Bcompound microscope
- Celectron microscope
- DVisionary
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Answer: D) Visionary
Q139. The telescope was invented by-
- AGalileo
- BGutenberg
- CEdison
- Dreceptive well
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Answer: A) Galileo
Q140. A concave lens is used for correction of-
- Acataract
- Blong view
- Cnearsightedness
- Dlong-sightedness
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Answer: C) nearsightedness
Q141. The sun appears elliptical before setting because-
- AAt that time the sun changes its shape.
- Blight gets scattered
- CRefraction of light has an effect on
- Ddiffraction of light has an effect on
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Answer: C) Refraction of light has an effect on
Q142. In what form does the signal travel in fibre optical communication?
- Alight wave
- Bradio waves
- Cmicrowave
- Delectric wave
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Answer: A) light wave
Q143. The stars twinkle-
- ACauses of refraction
- Bdue to reflection
- Cdue to polarization
- Ddue to scattering
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Answer: A) Causes of refraction
Q144. Which one of the following types of glass can cut off ultraviolet rays?
- Asoda glass
- BPyrex glass
- CJenna Glass
- DCrookes glass
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Answer: D) Crookes glass
Q145. Which of the following types of light is absorbed most rapidly by plants?
- APurple and orange
- Bblue and red
- CIndigo and yellow
- DYellow and purple
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Answer: B) blue and red
Q146. Consider the following phenomena: 1. Size of the Sun at dusk 2. Colour of the Sun at dawn 3. Appearance of the Moon at dawn 4. Twinkling of stars in the sky 5. Appearance of the Pole Star in the sky Which of the above are optical illusions?
- A1, 2 and 3
- B3, 4 and 5
- C1, 2 and 4
- D2, 3 and 5
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Answer: A) 1, 2 and 3
Q147. What is the name of the phenomenon (driven by the scattering of light) that causes mountain tops to turn pink or orange at sunrise and sunset?
- ABrillouin scattering
- Bstate of confusion
- CAlpenglow
- DBarrel distortion
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Answer: C) Alpenglow
Q148. Which of the following has the highest energy?
- Ablue light
- Bgreen light
- Cred light
- DYellow light
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Answer: A) blue light
Q149. When light waves pass from air to glass, which phenomena will be affected?
- Awavelength, shape and velocity
- Bvelocity and frequency only
- Cwavelength and frequency only
- Dwavelength and velocity only
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Answer: D) wavelength and velocity only
Q150. Light rays travel in a straight line, but they can travel along a curved path through an optical fiber. This is because:
- AThe fibers are very fine.
- BLight rays are absorbed at the entry end of the fibre and emitted at the output end.
- CScattering of light occurs inside the fibre
- DAs the ray passes through the fibre, successive total internal reflections occur.
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Answer: D) As the ray passes through the fibre, successive total internal reflections occur.
