An engineer, investigating the behavior of radio waves, builds a box 7.20 m long. Inside the box at one end is a small radio transmitter that emits radiation with a wavelength of 0.120 m. A receiver is placed at the other end, 7.20 m away. Assume both the transmitter and the receiver are on the floor of the box. The walls and floor of the box interior are treated to minimize reflection of radio waves. The ceiling of the box interior, however, is metal, so the radio waves can reflect off of it almost perfectly. The radio waves can take two paths from the transmitter to the receiver: a straight-line path, and a path that reflects off the ceiling of the box interior. Note that there is a phase shift when the waves reflect off the ceiling. (a) What is the minimum (nonzero) height of the box ceiling (in m) that could produce destructive interference between the direct and reflected waves at the receiver's location? m (b) What If? Some modern Wi-Fi antennas emit frequencies in the 5 GHz band. What would be the minimum height of the box (in m) required for destructive interference if the transmitter emitted waves at a frequency of 5.31 GHz?

An engineer, investigating the behavior of radio waves, builds a box 7.20 m long. Inside the box at one end is a small radio transmitter that emits radiation with a wavelength of 0.120 m. A receiver is placed at the other end, 7.20 m away. Assume both the transmitter and the receiver are on the floor of the box. The walls and floor of the box interior are treated to minimize reflection of radio waves. The ceiling of the box interior, however, is metal, so the radio waves can reflect off of it almost perfectly. The radio waves can take two paths from the transmitter to the receiver: a straight-line path, and a path that reflects off the ceiling of the box interior. Note that there is a phase shift when the waves reflect off the ceiling. (a) What is the minimum (nonzero) height of the box ceiling (in m) that could produce destructive interference between the direct and reflected waves at the receiver's location? m (b) What If? Some modern Wi-Fi antennas emit frequencies in the 5 GHz band. What would be the minimum height of the box (in m) required for destructive interference if the transmitter emitted waves at a frequency of 5.31 GHz?

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

Chapter27: Wave Optics

Section: Chapter Questions

Problem 38P

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