MCQOPTIONS
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MCQOPTIONS
This section includes 245 Mcqs, each offering curated multiple-choice questions to sharpen your UPSEE knowledge and support exam preparation. Choose a topic below to get started.
| 101. |
A converging lens with two curved surfaces has a front surface with radius of curvature 10 cm and the back surface with radius of curvature 20 cm. It is made of material with refractive index 1.5. The focal length of the lens is: |
| A. | 13.3 cm |
| B. | -13.3 cm |
| C. | 4.4 cm |
| D. | -4.4 cm |
| Answer» B. -13.3 cm | |
| 102. |
In figure, the optical fiber is l = 2 m long and has a diameter of d = 20 μm. If a ray of light is incident on one end of the fiber at angle θ1 = 40°, the number of reflections it makes before emerging from the other end is close to:(Refractive index of fiber is 1.31 and sin 40° = 0.64) |
| A. | 55000 |
| B. | 66000 |
| C. | 45000 |
| D. | 57000 |
| Answer» E. | |
| 103. |
A silicon monoxide (n = 1.45) film of 100 nm thickness is used to coat a glass camera lens (n = 1.56). What wavelength of light in the visible region will be most efficiently transmitted by this system? |
| A. | 628 nm |
| B. | 640 nm |
| C. | 580 nm |
| D. | 430 nm |
| Answer» D. 430 nm | |
| 104. |
Find the angle of a thin prism if its minimum angle of deviation is 2° and its refractive index is 1.5? |
| A. | 4° |
| B. | 3° |
| C. | 3.5° |
| D. | 0.5° |
| Answer» B. 3° | |
| 105. |
A well cut diamond appears bright because: |
| A. | it emit light |
| B. | of large density |
| C. | of total internal reflection |
| D. | it is crystal |
| Answer» D. it is crystal | |
| 106. |
An object is placed in front of a convex mirror. Which one of the following statements is correct? |
| A. | It will never form an inverted image |
| B. | The image moves towards the focus when the object moves towards the mirror. |
| C. | Depending on the position of the object with respect to the mirror, the image can be inverted and real. |
| D. | The size of the image becomes larger than that of the object when the object is placed at a distance equal to half the focal length. |
| Answer» B. The image moves towards the focus when the object moves towards the mirror. | |
| 107. |
For which of the following colours of monochromatic light, the fringe width in the interference fringe pattern observed in a Fresnel's biprism experiment will be maximum? |
| A. | Green |
| B. | Red |
| C. | Yellow |
| D. | Blue |
| Answer» C. Yellow | |
| 108. |
In case of a concave mirror, if an object is kept between principal focus F and pole P of the mirror, then which one of the following statements about the image is NOT correct? |
| A. | The image will be virtual |
| B. | The image will be enlarged or magnified |
| C. | The image will be formed at infinity |
| D. | The image will be erect |
| Answer» D. The image will be erect | |
| 109. |
In diffraction from a single slit, the angular width of the central maximum does not depend upon: |
| A. | Wavelength |
| B. | Width of the slit |
| C. | Distance between the slit and the screen |
| D. | The ratio of wavelength and the slit width |
| Answer» D. The ratio of wavelength and the slit width | |
| 110. |
In a single slit diffraction pattern, the intensity of the principal maximum is I0. On doubling the slit width, its intensity will be: |
| A. | I0 / 2 |
| B. | 4 I0 |
| C. | I0 |
| D. | 2 I0 |
| Answer» D. 2 I0 | |
| 111. |
If 'A' is the angle of a prism, 'i' is angle of incidence, 'e' is angle of emergence, then the angle of deviation 'δ' of light incident on the prism is equal to? |
| A. | i + e + A |
| B. | i - e + A |
| C. | i - e - A |
| D. | i + e - A |
| Answer» E. | |
| 112. |
A ray emanating from the object parallel to the principal axis of a convex lens after refraction _______________. |
| A. | passe s through the second principal focus |
| B. | passes through the center of curvature |
| C. | passes through the pole |
| D. | remains parallel to the principal axis |
| Answer» B. passes through the center of curvature | |
| 113. |
If the object is between focus and centre of curvature then the image obtained after reflection from a concave mirror is? |
| A. | between focus and centre of curvature, diminished, real and inverted |
| B. | beyond the centre of curvature, enlarged, real and erect |
| C. | between focus and centre of curvature, diminished, real and erect |
| D. | beyond the centre of curvature, enlarged, real and inverted |
| Answer» E. | |
| 114. |
A 1 cm object is placed perpendicular to the principal axis of a convex mirror of focal length 7.5 cm. Find its distance from the mirror if the image formed is 0.6 cm in size. |
| A. | 10 cm |
| B. | 12 cm |
| C. | 8 cm |
| D. | 5 cm |
| Answer» E. | |
| 115. |
Experimental observation in a single slit experiment shows that the intensity has a central maximum at θ = 0 and minima at θ = ______________.(where θ is the angle between the central line and the line joining the midpoint of the slit of width 'a' to any point P on the screen, λ is the wavelength of the lightand n = ±1, ±2, ±3, ....) |
| A. | nλ/a |
| B. | (n+1/2) λ/a |
| C. | na/λ |
| D. | (n+1/2)a/λ |
| Answer» B. (n+1/2) λ/a | |
| 116. |
Fraunhofer diffraction at a double slit is observed using the light of wavelength λ. The width of each slit is "a" and the width of the opaque portion between the two slits is 'b". The angular separation between any two consecutive maximum in the diffraction pattern is: |
| A. | λ/(a + b) |
| B. | λb/(a + b)2 |
| C. | λb/a2 |
| D. | λ a/b2 |
| Answer» B. λb/(a + b)2 | |
| 117. |
According to the New Cartesian Sign Convention, which one of the following is correct is respect of the formula \(\dfrac{1}{f} = \dfrac{1}{v}+ \dfrac{1}{u}\), where symbols have their usual meanings? |
| A. | It applies only to spherical mirrors |
| B. | It applies only to spherical lenses |
| C. | It applies to spherical mirrors as well as spherical lenses |
| D. | It is an invalid formula |
| Answer» B. It applies only to spherical lenses | |
| 118. |
A convex lens of focal length 20 cm produces images of the same magnification 2 when an object is kept at two distances x1 and x2 (x1 > x2) from the lens. The ratio of x1 and x2 is: |
| A. | 2 : 1 |
| B. | 3 : 1 |
| C. | 5 : 3 |
| D. | 4 : 3 |
| Answer» C. 5 : 3 | |
| 119. |
If the image of an object, formed by a concave mirror is virtual, erect and magnified, then the object is placed |
| A. | At the principle focus |
| B. | At the center of curvature |
| C. | Beyond the center of curvature |
| D. | Between the pole of the mirror and the principal focus |
| Answer» E. | |
| 120. |
Focal length of a plane mirror is: |
| A. | infinite |
| B. | very less |
| C. | indefinite |
| D. | zero |
| Answer» C. indefinite | |
| 121. |
A luminous object is placed at a distance of 40 cm from a converging lens of a focal length of 25 cm. The image obtained in the screen is ________. |
| A. | erect and magnified |
| B. | erect and smaller |
| C. | inverted and magnified |
| D. | inverted and smaller |
| Answer» D. inverted and smaller | |
| 122. |
An object is placed at a distance of 10 cm from a convex mirror of focal length 15 cm. The magnification is: |
| A. | 0.3 |
| B. | 0.6 |
| C. | -0.3 |
| D. | -0.6 |
| Answer» C. -0.3 | |
| 123. |
A sugar solution in a tube of length 20 cm, produces optical rotation of 13°. The sugar solution is diluted to one-third of its previous concentration. If the diluted solution is contained in a tube of length 30 cm, the optical rotation will be: |
| A. | 8.5° |
| B. | 6.5° |
| C. | 5.5° |
| D. | 7.5° |
| Answer» C. 5.5° | |
| 124. |
An object is placed at 10 cm in front of a concave mirror of radius of curvature 25 cm. Find the position of the image (in cm)? |
| A. | -50 |
| B. | 40 |
| C. | 50 |
| D. | -40 |
| Answer» D. -40 | |
| 125. |
Law of refraction was given by |
| A. | Maxwell |
| B. | Hygen |
| C. | Newton |
| D. | Snell |
| Answer» E. | |
| 126. |
In Fresnel's biprism experiment, if the distance between the slits is gradually increased, the fringe width in the interference fringe pattern obtained will: |
| A. | decrease |
| B. | increase |
| C. | remain unchanged |
| D. | first increase and then decrease |
| Answer» B. increase | |
| 127. |
A ray of light is incident on a very thin prism, the infractive index of the material of the prism is 1.6. The deviation of the ray of light is 6°. Find the angle of the prism. |
| A. | 5° |
| B. | 10° |
| C. | 8° |
| D. | 4° |
| Answer» C. 8° | |
| 128. |
Interference fringes are observed with a biprism of refracting angle 2° and refractive index 1.5 on a screen 100 cm away from it. If the distance between the source and the biprism is 20 cm and the fringe width is 0.10 mm, the wavelength of light used is: |
| A. | 5710 Å |
| B. | 5900 Å |
| C. | 5630 Å |
| D. | 5820 Å |
| Answer» E. | |
| 129. |
A ray of light AO in vacuum is incident on a glass slab at angle 60° and refracted at angle 30° along OB as shown in the figure. The optical path length of light ray from A to B is: |
| A. | \(\frac{{2\sqrt 3 }}{{\rm{a}}} + 2{\rm{b}}\) |
| B. | \(2a + \frac{{2{\rm{b}}}}{3}\) |
| C. | \(2a + \frac{{2{\rm{b}}}}{{\sqrt 3 }}\) |
| D. | \({\rm{\;}}2a + 2{\rm{b}}\) |
| Answer» E. | |
| 130. |
If a plane wavefront is incident on a convex lens then the emergent wavefront will be _______________ |
| A. | spherical with centre of the curvature of the surface |
| B. | conical with focus |
| C. | spherical with focus |
| D. | conical with centre of the curvature of the surface |
| Answer» D. conical with centre of the curvature of the surface | |
| 131. |
A real image of height twice that of the object was formed at a distance of 20 cm from the pole of a concave mirror. what is the focal length of the mirror ? |
| A. | 5.56 cm |
| B. | 6.67 cm |
| C. | 7.78 cm |
| D. | 8.89 cm |
| Answer» C. 7.78 cm | |
| 132. |
If a concave mirror of focal length 10cm is immersed in water, its focal length will ________. |
| A. | Be reduced |
| B. | Be increased |
| C. | Remain unchanged |
| D. | Change sign |
| Answer» D. Change sign | |
| 133. |
Maximum angle of diffraction in a plane transmission diffraction grating is: |
| A. | 90° |
| B. | 45° |
| C. | 180° |
| D. | 135° |
| Answer» B. 45° | |
| 134. |
An object is placed at the Centre of curvature of a concave mirror of focal length 16 cm. If the object is shifted by 8 cm towards the focus, the nature of the image would be |
| A. | Real and magnified |
| B. | Virtual and magnified |
| C. | Real and reduced |
| D. | Virtual and reduced |
| Answer» B. Virtual and magnified | |
| 135. |
A beam of transverse waves whose vibrations occur in all directions perpendicular to their direction of motion is |
| A. | polarised |
| B. | unpolarised |
| C. | resolved |
| D. | diffracted |
| Answer» C. resolved | |
| 136. |
A room window (consisting of a vertical sheet of plane glass) is exposed to direct sunshine at a strength of 1000 W/m2. The window is pointing due south, while the sun is in the southwest, 30° above the horizon. Estimate the amount of solar energy in W/m2 reflected by the window. Assume glass to be gray with ρ(reflectivity) = 0.08. |
| A. | 49 |
| B. | 490 |
| C. | 612.4 |
| D. | 61.2 |
| Answer» B. 490 | |
| 137. |
An upright object is placed at a distance of 40 cm in front of a convergent lens of focal length 20 cm. A convergent mirror of focal length 10 cm is placed at a distance of 60 cm on the other side of the lens. The position and size of the final image will be: |
| A. | 20 cm from the convergent mirror, same size as the object |
| B. | 40 cm from the convergent mirror, same size as the object |
| C. | 40 cm from the convergent lens, twice the size of the object |
| D. | 20 cm from the convergent mirror, twice the size of the object |
| Answer» B. 40 cm from the convergent mirror, same size as the object | |
| 138. |
If an object is placed between a concave mirror and F, what will be the type of image formed? |
| A. | Virtual |
| B. | Actual |
| C. | Complete |
| D. | Incomplete |
| Answer» B. Actual | |
| 139. |
In an interference experiment the ratio of amplitudes of coherent waves is \(\frac{{{a}_{1}}}{{{a}_{2}}}=\frac{1}{3}\). The ratio of maximum and minimum intensities of fringes will be: |
| A. | 2 |
| B. | 18 |
| C. | 4 |
| D. | 9 |
| Answer» D. 9 | |
| 140. |
A point object is placed at a distance of 30 cm from a convex mirror of focal length 30 cm. The image will form at |
| A. | infinity |
| B. | pole |
| C. | 15 cm behind the mirror |
| D. | 15 cm in front of the mirror |
| Answer» D. 15 cm in front of the mirror | |
| 141. |
Formation of real image using a biconvex lens is shown below. If the whole set up is immersed in water without disturbing the object and the screen positions, what will one observe on the screen? |
| A. | No change |
| B. | Magnified image |
| C. | Image disappears |
| D. | Erect real image |
| Answer» D. Erect real image | |
| 142. |
A man uses a concave mirror for shaving. He keeps his face at a distance of 25 cm from the mirror and gets an image which is 1.4 times enlarged. Find the focal length of the mirror. |
| A. | 87.5 cm |
| B. | 68.5 cm |
| C. | 24.5 cm |
| D. | 48.5 cm |
| Answer» B. 68.5 cm | |
| 143. |
An object is at a distance of 20 m from a convex lens of focal length 0.3 m. The lens forms an image of the object. If the object moves away from the lens at a speed of 5 m/s, the speed and direction of the image will be |
| A. | 3.22 × 10-3 m/s towards the lens |
| B. | 0.92 × 10-3 m/s away from the lens |
| C. | 2.26 × 10-3 m/s away from the lens |
| D. | 1.16 × 10-3 m/s towards the lens |
| Answer» E. | |
| 144. |
A solar cell is an example of |
| A. | photo conductive cell |
| B. | photo emissive cell |
| C. | photo voltaic cell |
| D. | photo radiation cell |
| Answer» D. photo radiation cell | |
| 145. |
How many colours of light are in white light colour? |
| A. | 1 |
| B. | 8 |
| C. | 7 |
| D. | 6 |
| Answer» D. 6 | |
| 146. |
If the object is at the centre of curvature, then the image obtained after reflection from a concave mirror is formed ________. |
| A. | at infinity, highly enlarged, real and inverted |
| B. | at the centre of curvature, same size, real and erect |
| C. | at the centre of curvature, same size, real and inverted |
| D. | at infinity, highly enlarged, real and erect |
| Answer» D. at infinity, highly enlarged, real and erect | |
| 147. |
Light waves are incident on an air-glass boundary. Some of the light waves are reflected and some are refracted in the glass. Which one of the following properties is the same for the incident wave and the refracted wave? |
| A. | Speed |
| B. | Direction |
| C. | Brightness |
| D. | Frequency |
| Answer» E. | |
| 148. |
A person is unable to read a newspaper without his glasses. He is most probably suffering from |
| A. | Myopia |
| B. | Presbyopia |
| C. | Astigmatism |
| D. | Hypermetropia |
| Answer» E. | |
| 149. |
A ray of light when refracted suffers change in velocity. In this context, which one among the following statements is correct? |
| A. | Velocity increases as the ray passes from a rarer to a denser medium |
| B. | Velocity decreases as the ray passes from a denser to a rarer medium |
| C. | Velocity decreases as the ray passes from a rarer to a denser medium |
| D. | Change of velocity does not depend on the nature of medium |
| Answer» D. Change of velocity does not depend on the nature of medium | |
| 150. |
A grating is used for |
| A. | Dispersion of the different wavelengths of a polychromatic light |
| B. | Combining two beams of light |
| C. | Splitting a beam of light |
| D. | Blocking the light |
| Answer» B. Combining two beams of light | |