1 Optical fibers work on the principle of: A Reflection B Refraction C Total internal reflection D Dispersion
2 The part of the eye that controls the amount of light entering is: A Retina B Cornea C Iris D Optic nerve
3 Which formula relates focal length, image distance, and object distance of a lens? A Magnification formula B Lens maker’s formula C Lens formula D Mirror formula
4 Which material is commonly used to make acoustic lenses? A Glass B Plastic C Quartz D Special solids or liquids
5 Gravitational lensing provides evidence for: A Wave nature of light B Quantum theory C General theory of relativity D Atomic structure
6 The bending of light around sharp edges is called: A Reflection B Refraction C Diffraction D Dispersion
7 The image formed on the retina of the human eye is: A Virtual and erect B Real and inverted C Virtual and inverted D Real and erect
8 The minimum angle of incidence for which total internal reflection occurs is called: A Angle of refraction B Critical angle C Angle of deviation D Polarizing angle
9 Which type of mirror always forms a virtual, erect, and diminished image? A Concave mirror B Convex mirror C Plane mirror D Parabolic mirror
10 Snell’s law relates the angles of incidence and refraction with: A Speed of light B Wavelength of light C Refractive indices D Intensity of light
11 Which mirror is used as a rear-view mirror in vehicles? A Concave mirror B Plane mirror C Convex mirror D Parabolic mirror
13 In a convex lens, parallel rays of light after refraction meet at: A Center of curvature B Optical center C Principal focus D Pole
14 Total internal reflection occurs when light travels from: A Denser to rarer medium B Rarer to denser medium C Vacuum to air D Air to glass only
15 The refractive index of a medium depends upon: A Color of the medium B Nature of the medium C Shape of the medium D Size of the medium
18 Which optical device uses total internal reflection to change the direction of light? A Lens B Plane mirror C Prism D Magnifying glass
19 Which lens is thicker at the center than at the edges? A Concave lens B Convex lens C Cylindrical lens D Plano-concave lens