21.8 A dish antenna with a diameter of 17.2 m receives (at normal incidence) a radio signal from a distant source, as shown in the figure below. The radio signal is a continuous sinusoidal wave with amplitude Emax = 0.28 µV/m. Assume the antenna absorbs all the radiation that falls on the dish. (A dish antenna on top of a tall tower extending above the trees. The dish points upward and to the left. Three parallel wavy arrows come downward and to the right toward the dish.) (a) What is the amplitude of the magnetic field in this wave? T(b) What is the intensity of the radiation received by the antenna? W/m2(c) What is the power received by the antenna? W

Unpolarized light passes through two ideal Polaroid sheets. The axis of the first is vertical and the axis of the second is at 40.0° to the vertical. What fraction of the incident light is transmitted? Three polarizing plates whose planes are parallel are centered on a common axis. The directions of the transmission axes relative to the common vertical direction are shown in the figure below. A linearly polarized beam of light with plane of polarization parallel to the vertical reference direction is incident from the left onto the first disk with intensity I₁ = = 11.0 units (arbitrary). Calculate the transmitted intensity I, when 0₁ = 21.0°, 0₂ = 41.0°, and 03 = 59.0°. Hint: Make repeated use of Malus's law. 1 units If= = I; 0₁ 02 03

An anstonomer on a planet orbiting the star Deneb wants to differentiate the reflected light by Earth from the light of the Sun. First, consider the area of Earths disk which reflects the Sun's intercepted light. Second, consider the surface area of a sphere with the same radius as Earths orbit around the Sun. Take the ratio of these two areas. Assume the Earths radius is 6400.0 km and is 1.3 x108 km from the Sun.

LASIK eye surgery uses pulses of laser light to shave off tissue from the cornea, reshaping it. A typical LASIK laser emits a 1.0-mmmm-diameter laser beam with a wavelength of 193 nmnm. Each laser pulse lasts 13 nsns and contains 1.1 mJmJ of light energy. What is the power of one laser pulse? During the very brief time of the pulse, what is the intensity of the light wave?

The intensity of a particular TV station’s signal is    I =1.01 x 10^(-13) W/m^2 when it arrives at a 28-cm  diameter satellite TV antenna.   A) Calculate the total energy received by the antenna during 5.0 hours and 40 minutes of viewing this station’s programs.   B)What is the amplitude of the field of the EM waves?   (E field)

A circular loop of wire can be used as a radio antenna. If an 19.8-cm-diameter antenna is located 3.00 km from a 88.9 MHz source with a total power of 60.1 kW, what is the maximum emf induced in the loop? The orientation of the antenna loop and the polarization of the wave are as shown in (Figure 1). Assume that the source radiates uniformly in all directions. Figure In vicinity of loop, wave propagates in +x-direction. In vicinity of loop. E has only a y-component and B has only a 2-component. E B 1 of 1 > Circular loop antenna lies in xy-plane. ▼ Answer Requested Part G Determine the time-dependent induced emf in the loop. Express your answer in terms of the variables BMax, w, k, d, z, and t. ▸ View Available Hint(s) IVE ΑΣΦ E(x, t) = Submit Previous Answers Request Answer X Incorrect; Try Again; 4 attempts remaining Part H Complete previous part(s) EVALUATE Part I Complete previous part(s) ?

A 4.25 m diameter university communications satellite dish receives TV signals that have a maximum electric field strength (for one channel) of 7.5 μV/m . (a)  What is the intensity of this wave in W/m2?  (b)  What is the power received by the antenna in W?  (c)  If the orbiting satellite broadcasts uniformly over an area of 1.50 × 1013 m2 (a large fraction of North America), how much power does it radiate in W?

Problem: A 3.46m diameter university communications satellite dish receives TV signals that have a maximum electric field strength (for one channel) of 7.87μV/m Part a: What is the intensity, in watts per squared meter, of this wave? Part b: What is the power, in watts, received by the antenna? part c: If the orbiting satellite broadcasts uniformly over an area of 1.50×1013m2(a large fraction of North America), how much power, in watts, does it radiate?

Problem 4:  Consider the 100-MHz radio waves used in an MRI device.  Part (a)  What is the wavelength, in meters, of these radio waves?  Part (b)  If the frequencies are swept over a ±14 MHz range centered on 100 MHz, what is the minimum, in meters, of the range of wavelengths emitted?  Part (c)  What is the maximum, in meters, of this wavelength range?

Two identical sources A and B emit in-phase plane radio waves with frequency 7.84E4 Hz and intensity 1.78E2 W/m2. A detector placed at location P closer to source B than source A detects a destructive interference. What is the intensity of the wave detected by the detector (in W/m2)?