CTEM-1 Which has higher frequency? A) Red light B) Violet-blue light C) Same frequencyD) Depends on how the light is madeCTEM-2An EM plane wave is described by 0 0ˆ ˆE E sin(k z t)x , B B sin(k z t)yw w= - = -v v Consider 3 antennas, labeled 1, 2, and 3. Antenna 1 is on the z axis.Antenna 2 is in the xz plane, above 1.Antenna 3 is is off the z-axis at the location shown.Rank the antennas by average signal strength received, from largest to smallest:A) 1 > 2 > 3 B) 1=2=3 C) 1 = 2 > 3c (z)E (x)B (y)123CTEM-3 A point source of radiation emits power Po isotropically (in all directions uniformly). A detector of area ad is located a distance R away from the source. What is the power p received by the detector?A: PRaod42B: PaRod22C: PaRodD: PRaod2E: None of these.detectoradPoRCTEM-4Two radio dishes (shaped like bowls) are receiving signals from a radio station which is sending out radio waves in all directions with power P. Dish 2 is twice as far away as Dish 1, but has twice the diameter. Which dish receives more power? (Dish 2 is not in the shadow of Dish 1.)A: Dish 1 B: Dish 2C: Both receive the same powerDish 1Dish 2CTEM-5 A parabolic dish focuses the EM radiation from asource into a beam of constant diameter D :The intensity of the light in the beam falls with distance R as:A) 21IR�B) 1IR� C) 01I constantR� =D) Something else.DcRCTEM-6 Light from a source is partially focused so that it diverges from the source uniformly over a cone of angle 200.The intensity of the light in the beam falls with distance R as:A) 21IR�B) N1I , N 2R� > C) N1I , N 2R� <D) 01I constantR� =D) Something else.cRCTEM-7 A polarized beam of light passes through three ideal polaroid filters. The filters, in order 1st, 2nd, 3rd, are tilted at 0o, 45o, and 90o with respect to the incoming beam's axis. Does any light get through the all the filters and come out the other side?A: Some light gets through.B: No light gets through. E cCTEM-8An unpolarized beam of light passes through 2 polaroid filters oriented at 45o with respect to each other. The intensity of the original beam is Io. What is the intensity of the light coming through both filters?(Hints: cos45o = 1/2. The average of cos2, average over all values of , iscos /21 2 .)A: (1/2)Io B: (1/4)Io C: (1/8)Io D: (1/16)Io E: None Io cCTEM-9 Under cover of night, a Girl scout signals her friends on a distant hill by alternately placing slabs of red or green Jell-O over her flashlight. This signal is most accurately described as.. A: Frequency modulation.B: Amplitude modulation.CTEM-10 A row of positive charges is stationary on the ground. A person with a gauss-meter (which measures the magnetic field) is running to the right along the row of charges, at thesame height as the charges and in front of them (in the diagram below). Does the person measure a non-zero B-field? A) Yes B) NoWhat is the direction of the B-field which the moving observer measures?A) Up B) Down C) Forward direction D) backward direction E) no direction, B-field
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