Exam 25: Electromagnetic Waves

The intensity of solar radiation near the earth is 1.4 × 10³ W/m². What force is exerted by solar radiation impinging normally on a 5.0 m² perfectly reflecting panel of an artificial satellite orbiting the earth?

Electromagnetic waves are

A polarizer is oriented at an angle θ to the vertical. If the vertically polarized beam of light of intensity 200 W/m² passes through the polarizer, what is the transmitted intensity of light for an angle of 20.0°?

A cordless phone operates at 900 MHz. What is the associated wavelength?

A vertically polarized beam of light of intensity 100 W/m² passes through a polarizer with its transmission axis at 40.0° to the vertical. What is the transmitted intensity of this beam of light?

If the magnetic field in a traveling electromagnetic wave has a maximum value of 16.5 nT, what is the maximum value of the electric field associated with it?

FIGURE 25-2 -For an xyz-coordinate system shown in Figure 25-2, if the E-vector is in the +z direction, and the B-vector is in the +x direction, what is the direction of propagation of the electromagnetic waves?

The magnitude of the electric field in the radiation field from an antenna is inversely proportional to the distance from the antenna.

FIGURE 25-3 -Figure 25-3 shows three polarizing disks having parallel planes with the direction of the transmission axis in each case. The disks are centered on a common axis. If a plane polarized beam of light is incident from left on the first disk with an intensity of 40 W/m². What is the transmitted intensity coming out of the third disk, when θ₁ = 10°, θ₂ = 40°, θ₃ = 70°?

Two objects are in all respects identical except for the fact that one was coated with a substance that is an excellent reflector of light while the other was coated with a substance that is a perfect absorber of light. You place both objects at the same distance from a powerful light source so they both receive the same amount of energy U from the light. The linear momentum these objects will receive is such that:

The wavelength of an electromagnetic wave is 600 nm. What is its frequency?

The maximum value of the electric field in an electromagnetic wave is 1.5 V/m. What is the maximum value of the magnetic field associated with this wave?

The intensity of the radiation field of an antenna is inversely proportional to the distance from the antenna.

In Fizeau's experiment for measuring the speed of light, the wheel has 475 notches. What rotational speed is required for the return beam of light to pass through the next notch? The time between successive notches is 6.65 × 10^-5 s.

Electromagnetic waves in a vacuum travel with the speed of light.

A beam of light travels a distance of 2900 m. How much time does it take?

An FM radio station broadcasts at 96.7 MHz. What is the wavelength associated with this broadcast?

The average magnetic energy density of an electromagnetic wave is 8.95 × 10^-5 J/m³. What is the magnetic field component of this wave?

An 8.000-mW laser beam emits a cylindrical beam of light 0.9000 mm in diameter. What is the rms value of the electric field in this beam?

The transverse nature of electromagnetic waves is apparent because