1 The breakdown strength of air is approximately: A 3 × 10^6 V/m B 3 × 10^3 V/m C 3 × 10^9 V/m D 3 × 10^2 V/m
2 Which device is used to detect electric charge? A Voltmeter B Ammeter C Galvanometer D Electroscope
4 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
7 The part of the eye that controls the amount of light entering is: A Retina B Cornea C Iris D Optic nerve
11 Constructive interference results in: A Decreased amplitude B Zero displacement C Increased amplitude D No effect
12 The angle between the incident ray and the normal is called: A Angle of reflection B Angle of deviation C Angle of incidence D Critical angle
13 Which law of reflection states that the angle of incidence is equal to the angle of reflection? A First law of reflection B Second law of reflection C Law of refraction D Snell’s law
14 Which lens is thicker at the center than at the edges? A Concave lens B Convex lens C Cylindrical lens D Plano-concave lens
15 Interference occurs when: A Two waves overlap B Wave changes speed C Wave reflects D Wave refracts
16 Gravitational lensing provides evidence for: A Wave nature of light B Quantum theory C General theory of relativity D Atomic structure
19 In a convex lens, parallel rays of light after refraction meet at: A Center of curvature B Optical center C Principal focus D Pole