radio station has two antennas. The antennas are a distance d apart, where d equals half the broadcast wavelength. The antennas are driven in phase with each other. Let the x-axis be the line that runs through the two antennas. The ngles are all measured counterclockwise from the +x-direction. (For the following, assume an observer is positioned a distance D far from the midpoint of the antennas, so that D >> d.) (a) In which directions is the strongest signal radiated? O 0°, 180° O 90°, 270° O 0°, 90°, 180°, 270° O 45°, 135°, 225°, 315° (b) In which directions is the weakest signal radiated? O 0°, 180° O 90°, 270° O 0°, 90°, 180°, 270°

radio station has two antennas. The antennas are a distance d apart, where d equals half the broadcast wavelength. The antennas are driven in phase with each other. Let the x-axis be the line that runs through the two antennas. The ngles are all measured counterclockwise from the +x-direction. (For the following, assume an observer is positioned a distance D far from the midpoint of the antennas, so that D >> d.) (a) In which directions is the strongest signal radiated? O 0°, 180° O 90°, 270° O 0°, 90°, 180°, 270° O 45°, 135°, 225°, 315° (b) In which directions is the weakest signal radiated? O 0°, 180° O 90°, 270° O 0°, 90°, 180°, 270°

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter24: Electromagnetic Waves

Section: Chapter Questions

Problem 23P

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A radio station has two antennas. The antennas are a distance d apart, where d equals half the broadcast wavelength. The antennas are driven in phase with each other. Let the x-axis be the line that runs through the two antennas. The angles are all measured counterclockwise from the +x-direction. (For the following, assume an observer is positioned a distance D far from the midpoint of the antennas, so that D ≫ d.) (a) In which directions is the strongest signal radiated? 0°, 180° 90°, 270° 0°, 90°, 180°, 270° 45°, 135°, 225°, 315° (b) In which directions is the weakest signal radiated? 0°, 180° 90°, 270° 0°, 90°, 180°, 270° 45°, 135°, 225°, 315°
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