4) Which of these electromagnetic waves has the shortest wavelength? A. radio waves B. infrared waves C. X rays D. ultraviolet waves E.

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1 1)Electromagnetic waves consist of compressions and rarefactions. B. vibrating electric and magnetic fields. C. particles of light energy. D. high-frequency gravitational waves. 2) Electromagnetic waves. always travel at the same speed. B. need a medium to travel through. C. can travel through a vacuum. D. cannot travel through the vacuum of outer space. 3) The main difference(s) between a radio wave and a light wave is(are) its. speed. B. wavelength. C. frequency. both a and b E. both b and c 4) Which of these electromagnetic waves has the shortest wavelength?. radio waves B. infrared waves C. X rays D. ultraviolet waves E. light waves

2 5) Compared to ultraviolet waves, the wavelength of infrared waves is. shorter B. longer. C. faster. D. slower E. the same 6) Compared to radio waves, the velocity of visible light waves in a vacuum is. less. B. more. C the same. 7) ll of the waves listed below are a part of the electromagnetic spectrum except. sound waves. B X rays. C. gamma rays. D. light waves. E. radio waves. 8) Materials generally become warmer when light is. absorbed by them. B. reflected by them. C. transmitted by them. D. all of these E. none of these. 9) If a light signal and a radio signal were transmitted simultaneously from a nearby star, the first signal to reach the Earth would be. the radio signal. B. the light signal. c. neither: they would both reach the earth at the same time. 10) Light waves traveling through the vacuum of space have a speed that's equal to. 3.0 X 10 to power of (3) m/s. B. 5 X 10 to power of (6) m/s. C. 3.0 X 10 to power of (8) m/s. D. 9.0 X 10 to power of (9) m/s. E. a number that's too high to measure. 11) Color depends on what characteristic of light?. its frequency B. its wavelength C. both of these D. neither of these 12) The color of an object is the same as the light that is. transmitted. B. absorbed. C. reflected. D. all of these. E. none of these.

3 13)Sunsets are red because the lower frequencies of light. are scattered by larger particles in the atmosphere. B. are refracted by larger particles in the atmosphere. C. are reflected by clouds and relatively large particlesin the atmosphere. D. survive being scattered in the atmosphere. 14) The fact that you can get sunburned while submerged in water is evidence thatwater. absorbs infrared light. B. transmits infrared light. C. absorbs ultraviolet light. D. transmits ultraviolet light. 15) The worst thing you can do for the health of a green-leafed plant is to illuminate it with only. red light. B. green light. C. blue light. D. all are equally naughty. E. none of these. 16) The effect in which white light separates into different colors is called. magnification. B. refraction. C. reflection. D. dispersion. 17) Diffraction is more pronounced through relatively. small openings. B. large openings C. same for each. 18) Waves diffract the most when their wavelength is short. B. long. C. both diffract the same. 19) Diffraction is a result of. refraction. B. reflection. C. interference. D. polarization. E. dispersion. 20) Interference is a property of. light waves. B. sound waves. C water waves. D. all of these. E. none of these. Use the diagram below, answer question ) Polarization is a property of. transverse waves. B. longitudinal waves. C.both. D. neither.

4 22) Light will not pass through a pair of polarizing lenses when their axes are. parallel. B. perpendicular. C. 45 degrees to each other. D. two of these. E. all of these. 23) The incident light ray, the reflected light ray, and the normal line between them. form two angles, with the incident angle greater than the angle of reflection. B. form two angles, with the incident angle less than the angle of reflection. C. form two angles, with the incident angle equal to the angle of reflection. 24) When light reflects from a surface, there is a change in its. frequency. B. wavelength. C. speed. D. all of these. E. none of these. Using the figure below, answer the next question: 25) When light passes through air into glass, its angle of refraction is. less than its angle of incidence. B. the same as its angle of incidence. C. more than its angle of incidence. D. can be more or less than its angle of incidence. 26) Light travels fastest in. warm air. B. cool air. C. a vacuum. 27) Refraction results from differences in light's. frequency. B amplitude. C. speed. D. all of these. E. none of these. 28) Light refracts when traveling from air into glass because light. travels at the same speed in air and in glass. B. frequency is greater in air than in glass. C. frequency is greater in glass than in air. D. travels slower in glass than in air. 29) Hz electromagnetic wave propagates in carbon tetrachloride with a speed of m/s. The wavelength of the wave in carbon tetrachloride is closest to: ) 1070 nm B) 1290 nm C) 1200 nm D) 967 nm E) 1420 nm

5 30) Hz electromagnetic wave propagates in carbon tetrachloride with a speed of m/s. The wavelength of the wave in vacuum is closest to: ) 413 nm B) 368 nm C) 505 nm D) 459 nm E) 314 nm 31) Hz electromagnetic wave propagates in carbon tetrachloride with a speed of m/s. The relative magnetic permeability of carbon tetrachloride is The dielectric constant of carbon tetrachloride at a frequency of Hz is closest to: ) 2.52 B) 1.38 C) 1.76 D) 2.14 E) 1 32) planar electromagnetic wave is propagating in the positive x-direction. t a certain point Pand at a given instant, the electric field of the wave is given by E = -j 82 mv/m. The magneticvector of the wave, at the point P at that instant is closest to: ) ( T) k B) ( T) k C) ( T) j D) ( T) j E) ( T) k 33) planar electromagnetic wave is propagating in the positive x-direction. t a certain point Pand at a given instant, the electric field of the wave is given by E = -j 12 mv/m. The Poyntingvector at the point P at that instant is closest to: ) ( W/m 2 ) i B) ( W/m 2 ) i C) ( W/m 2 ) k D) ( W/m 2 ) i E) ( W/m 2 ) i 34) The magnitude of the Poynting vector of a planar electromagnetic wave has an average value of724 mw/m 2. The maximum value of the magnetic field in the wave is closest to: ) T B) T C) T D) T E) T 35) The magnitude of the Poynting vector of a planar electromagnetic wave has an average value of939 mw/m 2. The wave is incident upon a rectangular area, 1.5 m by 2.0 m, at right angles. The total energy that traverses the area in a time interval of one minute is closest to: ) 210 J B) 340 J C) 300 J D) 170 J E) 250 J

6 36) n 800-kHz radio signal is detected at a point 4.5 km distant from a transmitter tower. The electric field amplitude of the signal at that point is 630 mv/m. ssume that the signal power is radiated uniformly in all directions and that radio waves incident upon the ground are completely absorbed. The magnetic field amplitude of the signal at that point, in nt, is closest to: ) 2.5 B) 2.1 C) 1.7 D) 1.3 E) ) n 800-kHz radio signal is detected at a point 8.5 km distant from a transmitter tower. The electric field amplitude of the signal at that point is 900 mv/m. ssume that the signal power is radiated uniformly in all directions and that radio waves incident upon the ground are completely absorbed. The average electromagnetic energy density at that point is closest to: ) J/m 3 B) J/m 3 C) J/m 3 D) J/m 3 E) J/m 3 38) n 800-kHz radio signal is detected at a point 2.7 km distant from a transmitter tower. The electric field amplitude of the signal at that point is 360 mv/m. ssume that the signal power is radiated uniformly in all directions and that radio waves incident upon the ground are completely absorbed. The intensity of the radio signal at that point is closest to: ) W/m 2 B) W/m 2 C) W/m 2 D) W/m 2 E) W/m 2 39) n 800-kHz radio signal is detected at a point 9.1 km distant from a transmitter tower. The electric field amplitude of the signal at that point is 440 mv/m. ssume that the signal power is radiated uniformly in all directions and that radio waves incident upon the ground are completely absorbed. The average total power radiated by the transmitter is closest to: ) W B) W C) W D) W E) W Figure 32.1 radiometer has two square vanes (1 cm by 1 cm), attached to a light horizontal cross arm, and pivoted about a vertical axis through the center. The center of each vane is 6 cm from the axis. One vane is silvered and it reflects all radiant energy incident upon it. The other vane is blackened and it absorbs all incident radiant energy. Radiant energy, which has an intensity of 300 W/m 2, is incident normally upon the vanes.

7 40) In Fig. 32.1, the radiant power absorbed by the blackened vane is closest to: ) 0.03 W B) 0.06 W C) 0.05 W D) 0.04 W E) 0.09 W 41) In Fig. 32.1, the radiation pressure on the blackened vane is closest to:) 1-10 Pa B) Pa C) Pa D) Pa E) Pa 42) In Fig. 32.1, the torque on the vane assembly, about the vertical axis, is closest to:) zero B) N m C) N m D) N m E) N m 43) The wavelength of visible light ranges from 400 nm to 700 nm. The highest frequency of visiblelight is closest to: ) Hz B) Hz C) Hz D) Hz E) Hz 44) If the z-component of the magnetic field of an electromagnetic wave traveling in the x-directionthrough vacuum obeys the equation B z = (1.25 µt) cos[(3800 m-1)x -( rad/s)t], then the largest that the y-component of the electric field can be is closest to: ) 375 N/C B) N/C C) N/C D) N/C E) N/C Situation 32.1 microwave oven operates at a frequency of 2400 MHz. The height of the oven cavity is 25 cm and the base measures 30 cm by 30 cm. ssume that microwave energy is generated uniformly on the upper surface of the cavity and propagates directly downward toward the base. The base is lined with a material that completely absorbs microwave energy. The total microwave energy content of the cavity is 0.50 mj. 45) In Situation 32.1, the power output of the microwave oven is closest to: ) 700 W B) 550 W C) 600 W D) 650 W E) 500 W

8 46) In Situation 32.1, 2 the intensity of the microwave beam is closest to: ) 5200 W/m B) 7200 W/m 2 C) 6200 W/m 2 D) 6700 W/m 2 E) 5700 W/m 2 47) In Situation 32.1, the electric field amplitude is closest to:) 1600 V/m B) 2500 V/m C) 1900 V/m D) 2200 V/m E) 2800 V/m 48) In Situation 32.1, the force on the base due to the radiation is closest to:) N B) N C) N D) N E) N 49) Hz laser emits a 8.7-µs pulse, 5.0 mm in diameter, with a beam energy density of 0.21 J/m 3. The number of wavelengths in the length of the beam is closest to: ) B) C) D) E) ) Hz laser emits a 2.0-µs pulse, 5.0 mm in diameter, with a beam energy density of 0.75 J/m 3. The power emitted by the laser is closest to: ) 4.4 kw B) 13 kw C) 22 kw D) 8.9 kw E) 18 kw 51) Hz laser emits a 7.7-µs pulse, 5.0 mm in diameter, with a beam energy density of 0.51 J/m 3. The amplitude of the electric field of the emitted waves is closest to: ) V/m B) V/m C) V/m D) V/m E) V/m 52) 8.6 x Hz laser emits a 9.7 µs pulse, 5.0 mm in diameter, with a beam energy density of 0.85 J/m 3. The average Poynting vector magnitude of the beam is closest to: ) W/m 2 B) W/m 2 C) W/m 2 D) W/m 2 E) W/m 2

9 Situation 32.2 standing planar electromagnetic wave is established in a resonant cavity formed by two parallel conducting plates that are 12 cm apart. The number of electric field antinoidal planes, including the cavity walls, in the standing wave is three. 53) In Situation 32.2, the frequency of the electromagnetic wave in GHz (G = giga = 10 ), is closest 9 to: ) 5.00 B) 3.75 C) 6.25 D) 2.50 E) ) In Situation 32.2, the number of antinoidal planes for the magnetic field is: ) 4 B) 3 C) 5 D) 6 E) 2 55) In Situation 32.2, the smallest distance between an electric field antinoidal plane and a magneticfield antinoidal plane, in cm, is closest to: ) zero B) 2.0 C) 1.0 D) 3.0 E) ) certain glass has an index of refraction of 1.44 at a wavelength of 560 nm in vacuum. What isthe effective dielectric constant at the corresponding frequency? ) 2.07 B) 1.44 C) 3.66 D) 1.98 E) ) Electromagnetic standing waves are set up in a conducting cavity resonator in the form of a hollow metal box. The waves bounce back and forth between two parallel surfaces separated by 0.80 cm. What is the minimum resonant frequency for such a resonator? ) 15.5 GHz B) 4.42 GHz C) 18.8 GHz D) 12.4 GHz E) 3.30 GHz Situation 32.3 The y-component of the electric field of an electromagnetic wave traveling in the +x-direction through vacuum obeys the equation E y = (375 N/C) cos[ks - ( rad/s)t]. 58) In Situation 32.3, the wavelength of the electromagnetic wave is closest to: ) 2.72 µm B) 1.36 µm C) 8.57 µm D) 17.1 µm E) µm 59) In Situation 32.3, the largest that the x-component of the magnetic field of the wave can be is closest to: ) 1.36 µt B) 1.25 µt C) T D) T E) 0.00 µt 60) In Situation 32.3, the largest that the z-component of the magnetic field of the wave can be isclosest to: ) T B) 1.25 µt C) 0.00 µt D) 1.36 µt E) T

10 61. Consider: radio waves (r), visible light (v), infrared (i), x-rays (x), and ultraviolet (u). In order of decreasing wavelength, they are: ) r, v, i, x, u B) r, i, v, u, x C) i, r, v, u, x D) i, v, r, u, x E) r, i, v, x, u 62. n electromagnetic wave is generated by: ) any moving charge B) any accelerating charge C) only a charge with changing acceleration D) only a charge moving in a circle E) only a charge moving in a straight line 63. The index of refraction of a substance is: ) the speed of light in the substance B) the angle of refraction C) the angle of incidence D) the speed of light in vacuum divided by the speed of light in the substance E) measured in radians 64. Which diagram below illustrates the path of a light ray as it travels from a given point X in air to another given point Y in glass? ) I B) II C) III D) IV E) V 65. ray of light passes through three media as shown. The speeds of light in these media obey: ) v1 > v2 > v3 C) v3 > v1 > v2 B) v3 > v2 > v1 D) v2 > v1 > v3 E) v1 > v3 > v2 66. Radio waves of wavelength 300 m have a frequency of: ) 10 6 khz B) 500 khz C) 1 MHz D) 9 MHz E) 108 khz 67. clear sheet of polaroid is placed on top of a similar sheet so that their polarizing axes make an angle of 30 with each other. The ratio of the intensity of emerging light to incident unpolarized light is: ) 1:4 B) 1:3 C) 1:2 D) 3:4 E) 3:8 68. n unpolarized beam of light has intensity I0. It is incident on two ideal polarizing sheets. The angle between the axes of polarization of these sheets is θ. Find θ emerging light has intensity I0/4: ) sin 1 (1/2) B) sin ( ) C) cos 1 (1/2) D) cos ( 1 2 ) E) tan 1 (1/4) if the

11 69. The index of refraction for diamond is 2.5. Which of the following is correct for the situation shown? ) (sin a)/(sin b) = 2.5 B) (sin b)/(sin d) = 2.5 C) (cos a)/(cos c) = 2.5 D) (sin a)/(sin c) = 1/(2.5) E) a/c = The index of refraction of benzene is The critical angle for total internal reflection, at a benzene-air interface, is about: ) 56 B) 47 C) 34 D) 22 E) The separation of white light into colors by a prism is associated with: ) total internal reflection B) partial reflection from each surface C) variation of index of refraction with wavelength D) a decrease in the speed of light in the glass E) selective absorption of various colors ft woman wishes to see a full length image of herself in a plane mirror. The minimum length mirror required is: ) 5 ft B) 10 ft C) 2.5 ft D) 3.54 ft E) no answer: the farther away she stands the smaller the required mirror length 73. parallel beam of monochromatic light in air is incident on a plane glass surface. In the glass, the beam: ) remains parallel B) undergoes dispersion C) becomes diverging D) follows a parabolic path E) becomes converging 74. The image produced by a convex mirror of an erect object in front of the mirror is always: ) virtual, erect, and larger than the object B) virtual, erect, and smaller than the object C) real, erect, and larger than the object D) real, erect, and smaller than the object E) none of the above 75. n erect object is located between a concave mirror and its focal point. Its image is: ) real, erect, and larger than the object B) real, inverted, and larger than the object C) virtual, erect, and larger than the object D) virtual, inverted, and larger than the object E) virtual, erect, and smaller than the object

12 (76) The sum delivers 3 Wm -2 of electromagnetic flux to earth s surface. The totalpower that 10 is incident on a roof of dimension 8m x 20m will be () w (B) w (C) w (D) w (77) Bolometer is used to detect. () infrared rays (B) ultraviolet rays (C) x rays (D) rays (78) Range of frequency of microwaves is about. ()530kHz to 1710kHz (B)54MHz to 890MHz (C) 3GHz to 300GHz (D) Hz to (79) SI unit of displacement current is () coulomb (B)ampere (C)faraday (D) Hz (80) The frequencies of x rays, rays and ultraviolet rays are respectively p, q and rthen ()p<q, q>r (B) p>q, q>r (C)p>q, q<r (D)p<q, q<r (81) t room temperature, if the relative permitivity of water is 80 and the realtivepermiability be then the velocity of light in water is m/s () (B) (C) (D) (82) If the electric field associated with a radiation of frequency 10MHz is E=10sin(kxω t)mv/m then its energy density is εo= C 2 N -1 m -2 Jm 3 ( () (B) (C) (D) (83) In an electromagnetic wave in free space, the direction of electric field vector E is along y axis and magnetic field vector B is along z axis then which of the following is true () E B E (B) E B B (C) E B B 0 (D) none of these (84) When a plane electromagnetic wave travels in vaccum, the average electric energy density is given by (Eo is the amplitude of the electric field) () oeo (B) Eo o (C) 2 o Eo 2 (D) 4 o Eo 2 (85) In a plane electromagnetic wave, the electric field oscillates sinusoidaly at a frequency of Hz. if the peak value of electric field is 60 Vm 1 the average energy density (in Jm -3 ) of the magnetic field of the wave will be (given o = Tm/) () (B) (C) (D) )

13 x (86) Which of the following pairs of the component of space and time varying E = Ε i ˆ + Eyj ˆ + Ezkˆ B = B ˆi + Byj ˆ + Bzkˆ would generate a plane electromagnetic wave travelling in +ve y direction () B i, E i x z and x (B) (87) Infrared radiations are detected by E i, B i y z (C) E i, B i x x (D) E i, B i () spectrometer (B)bolometer (C)photocells (D)geiger tubes (88) Electromagnetic wave is produced by oscillating electric and magnetic fields and B E. Choose only the incorrect statement from the following () E is perpendicular to B. (B) E is perpendicular to the direction of propagation of the wave (C) B is perpendicular to the direction of propagation of the wave (D) E is parallel to B (89) The potential difference between the plates of a parallel plate capacitor is charg-ing at the rate of 10 6 Vs 1. If the capatance is 2 F. The displacement current in the dielectric of the capacitor will be () 4 (B)3 (C)2 (D)1 (90) Which of the following electromagnetic wave has the least frequency? () radiowave (B) infrared radiation (C)microwave (D)x rays (91) Which of the following electromagnetic wave has the least wavelength? () rradiowave (B)visible wave (C) ultraviolet rays (D)micro-waves (92) Which of the following waves are not transverse in nature? () light emitted from a sodium lamp (B) sound waves travelling in air (C) xrays from an x ray machine (D) microwaves used in radar (93) n electromagnetic wave () can be deflected by electric field (B) can be deflected by magnetic field (C) can be deflected bye both electric and magnetic field (D) none of these (94) When an electromagnetic wave encounters a dielectric medium, the transmittedwave has () same frquency but different amplitude (B) same amplitude but different frequency (C) same frequency and amplitude (D) different frequency and amplitude z x

14 (95) ccording to Maxwell, a changing electric field produces () emf (B)radiation pressure (C) electric current (D)magnetic field (96) was the first to predict the existence of electromagnetic waves () Maxwel (B) Faraday (C)mpere (D) hertz (97) If the earth were not having atmosphere, its temperature. () would have been low (B) would have been high (C)would hav remain constant (D) none of these (98) is responsible for the green house effect () infrared rays (B)ultraviolet rays (C)x raya (D)radiowaves (99) The dimensional formula of energy density is () M 1 L 0 T 2 (B) M 1 L 1 T 2 (C) M 1 L 1 T 3 (D) M 1 L 0 T 3 100) Unit of oc is same as that of ()current (B)resistance (C)electric charge (D) velocity

15 nswer 1.b 2. c 3. e 4. c 5. b 6. c 7. a 8. a 9. c 10. c 11. c 12. c 13. d 14. d 15. b 16. d 17. a 18. b 19. c 20. d 21. a 22. b 23. c 24. e 25. a 26. c 27. c 28. d 29) D 30) D 31) D 32) 33) 34) 35) D 36) B 37) C 61.B 62.B 63.D 64.E 65. C 66.C 67.E 68.D 69.D 70.C 71.C 72.C B 75.C 38) 39) B40) 41) B42)B43) 44) 45) C 46)D47) D48) 49) E50) 51) E52) C53) B54) 55)B56) 57) C58) C59) E60)B D C 79 B B 82 C B B D C C B D D 99 B 100 B