At a distance of 25m from an isotropic 100 MHz radio source the intensity is 120W/m2 (a) What is the rms electric field at 25m? (b) Over a 2 hour period, what is the momentum given to a 4cm´4cm surface (at the 25m distance) perpendicular to the source that reflects 3/4 of the energy? (c) What is the total power transmitted by the source?

At a distance of 25m from an isotropic 100 MHz radio source the intensity is 120W/m2 (a) What is the rms electric field at 25m? (b) Over a 2 hour period, what is the momentum given to a 4cm´4cm surface (at the 25m distance) perpendicular to the source that reflects 3/4 of the energy? (c) What is the total power transmitted by the source?

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter34: Maxwell’s Equations And Electromagnetic Waves

Section: Chapter Questions

Problem 38PQ

See similar textbooks

Similar questions

A radio station broadcasts its radio waves with a power of 50,000 W. What would be the intensity of this signal if it is received on a planet orbiting Proxima Centuri, the closest star to our Sun, at 4.243 ly away?
A 2.0-mW helium-neon laser transmits a continuous beam of red light of cross-sectional area 0.25 cm2. If the beam does not diverge appreciably, how would its rms electric field vary with distance from the laser? Explain.
Two handheld radio transceivers with dipole antennas are separated by a large fixed distance. If the transmitting antenna is vertical, what fraction of the maximum received power will appear in the receiving antenna when it is inclined from the vertical by (a) 15.0°, (b) 45.0°, and (c) 90.0°?
Project Seafarer was an ambitious program to construct an enormous antenna, buried underground on a site about 10000 km2 in area. Its purpose was to transmit signals to submarines while they were deeply submerged. If the effective wavelength were 4.6 × 104 Earth radii, what would be the (a) frequency and (b) period of the radiation emitted? Ordinarily, electromagnetic radiations do not penetrate very far into conductors such as seawater. Take the Earth's radius to be 6370 km.
A radio station on the surface of the earth radiates an EM-wave with an average total power of 50 kilowatts. Assuming the transmitter radiates equally in all directions (not in real life), find the amplitudes Emaxmax and Bmaxmax detected by a satellite at a distance of 100 km from the antenna?
The microwave radiation left over from the Big Bang has a maximummagnetic field strength of 2.33 x 10 -10 T. What is the correspondingmaximum electric field strength of the wave?
Project Seafarer was an ambitious program to construct an enormous antenna, buried underground on a site about 10 000 km2 in area. Its purpose was to transmit signals to submarines while they were deeply submerged. If the effective wavelength were 1.0 * 10^4 Earth radii, what would be the (a) frequency and (b) period of the radiations emitted? Ordinarily, electromagnetic radiations do not penetrate very far into conductors such as seawater, and so normal signals cannot reach the submarines.
AM radio waves can be produced by a marconi anthenna, whose length must be one-fourth of the wave's wavelength. What must be the length, in meters, of the antenna to produce a frquency of 630kHz?
At what distance from a 125 W electromagnetic-wave point source does Emax = 15.1 V/m?
The star Sirius is much hotter than the sun, with a peak wavelength of 290 nm compared to the sun’s 500 nm. It is also larger, with a diameter 1.7 times that of the sun. By what factor does the energy emitted by Sirius exceed that of the sun?
At what distance from a 100-W electromagnetic wave point source does Emax = 15.0 V/m?
Two friends are playing with hand-held radio transceivers which have dipole antennas. If the antenna of the transmitting radio is vertical, and the antenna of the receiving radio is at an angle ? to the vertical, what is the received power as a percentage of the maximum possible received power at the receiving antenna in the following cases?