Exam 24: Electromagnetic Waves

24-3 The figure shows the time variation of the magnitude of the electric field of an electromagnetic wave produced by a wire antenna. -To which region of the electromagnetic spectrum does this wave belong?

Linearly polarized light is incident of a sheet of polarizing material.The angle between the transmission axis and the incident electric field is 44°.What percentage of the incident intensity is transmitted?

What is the rms value of the electric field? Assume that the figure shows the peak value of .

24-1 A linearly polarized electromagnetic wave is sent through two sheets of polarizing material.The first sheet, A, is oriented so that its transmission axis makes an angle of 30° with respect to the incident electric field of the wave.The second sheet, B, is oriented so that its transmission axis makes an angle of 90° with the incident electric field of the wave.The incident beam has an electric field of peak magnitude E₀ and average intensity S₀. -An FM radio station emits an electromagnetic wave which is received by a circuit containing a 3.33 × 10^-7 H inductor and a variable capacitor set at 7.31 × 10^-12 F.What is the frequency of the radio wave?

When a radio telescope observes a region of space between two stars, it detects electromagnetic radiation that has a wavelength of 0.21 m.This radiation was emitted by hydrogen atoms in the gas and dust located in that region.What is the frequency of this radiation?

A linearly polarized beam of light is incident upon a group of three polarizing sheets which are arranged so that the transmission axis of each sheet is rotated by 45° with respect to the preceding sheet as shown.What fraction of the incident intensity is transmitted?

An incandescent light bulb radiates uniformly in all directions with a total average power of 1.0 × 10² W.What is the maximum value of the magnetic field at a distance of 0.50 m from the bulb?

What is the rms value of the magnetic field? Assume that the figure shows the peak value of .

24-3 The figure shows the time variation of the magnitude of the electric field of an electromagnetic wave produced by a wire antenna. -Determine the rms value of the electric field magnitude.

Which one of the following colors of visible light has the highest frequency?

Two polarizing sheets have their transmission axes parallel so that the intensity of unpolarized light transmitted through both of them is a maximum.Through what angle must either sheet be rotated if the transmitted intensity is 25 % of the incident intensity?

A radio wave sent from the surface of the earth reflects from the surface of the moon and returns to the earth.The elapsed time between the generation of the wave and the detection of the reflected wave is 2.6444 s.Determine the distance from the surface of the earth to the surface of the moon.Note: The speed of light is 2.9979 × 10⁸ m/s.

A laser uniformly illuminates an area with green light that has an average intensity of 550 W/m².What is the rms value of the electric field of this light?

Which one of the following will not generate electromagnetic waves or pulses?

24-1 A linearly polarized electromagnetic wave is sent through two sheets of polarizing material.The first sheet, A, is oriented so that its transmission axis makes an angle of 30° with respect to the incident electric field of the wave.The second sheet, B, is oriented so that its transmission axis makes an angle of 90° with the incident electric field of the wave.The incident beam has an electric field of peak magnitude E₀ and average intensity S₀. -What is the peak value of the electric field amplitude after it goes through sheet A?

An astronomer observes electromagnetic waves emitted by oxygen atoms in a distant galaxy that have a frequency of 5.710 × 10¹⁴ Hz.In the laboratory on earth, oxygen atoms emit waves that have a frequency of 5.841 × 10¹⁴ Hz.Determine the relative velocity of the galaxy with respect to the astronomer on the earth.Note: The speed of light is 2.9979 × 10⁸ m/s.

24-1 A linearly polarized electromagnetic wave is sent through two sheets of polarizing material.The first sheet, A, is oriented so that its transmission axis makes an angle of 30° with respect to the incident electric field of the wave.The second sheet, B, is oriented so that its transmission axis makes an angle of 90° with the incident electric field of the wave.The incident beam has an electric field of peak magnitude E₀ and average intensity S₀. -What is the average intensity of the wave after it passes through A?

The amplitude of the electric field component of an electromagnetic wave is increased from E to 3E.What is the corresponding change in the intensity of the wave?

What is the correct order, beginning with shortest wavelength and extending to the longest wavelength, of the following colors in the visible light spectrum: blue, green, red, violet, and yellow?

The electric field E of an electromagnetic wave traveling the positive x direction is illustrated in the figure.This is the wave of the radiation field of an antenna.What are the direction and the phase relative to the electric field of the magnetic field at a point where the electric field is in the negative y direction? Note: The wave is shown in a region of space that is a large distance from its source.