adio antenna (also called a Marconi antenna) consists of a long conductor of one quarter the length of the transmitted wavelength. The lower end of the antenna is connected to a conducting ground plane (often simply the Earth) which reflects the transmitted signal, creating an effective antenna length of a half wavelength. (a) What must be the height of the antenna (in m) for a radio station broadcasting at 569 kHz? (b) What must be the height of the antenna (in m) for radio stations broadcasting at 1,750 kHz?

VHF, or very high frequency, refers to radio frequency electromagnetic waves in the range 30 to 300 MHz. In the U.S., television stations broadcast channels 2 through 13 in the VHF range between 54.0 MHz and 216 MHz, with ranges 72.0 to 76.0 MHz and 88.0 to 174 MHz not utilized for TV broadcasting. Each channel has a frequency width of 6.00 MHz. The table below gives the lower and upper frequency of each channel. Channel Lower edge (MHz) Upper edge (MHz) 2 3 4 5 6 7 8 9 10 11 12 13 54 60 66 76 82 174 180 186 192 198 204 210 m m m m 60 66 m 72 m 82 88 180 186 (a) Calculate the broadcast wavelength range for channel 2. (Enter your answers from smallest to largest, in m.) smallest value largest value 192 198 204 (b) Calculate the broadcast wavelength range for channel 3. (Enter your answers from smallest to largest, in m.) smallest value largest value 210 216 (c) Calculate the broadcast wavelength range for channel 5. (Enter your answers from smallest to largest, in m.) smallest value…

What inductance must be connected to a 25 pF capacitor in an oscillator capable of generating 490 nm (i.e., visible) electromagnetic waves?

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?

The rainbow of visible colors in the electromagnetic spectrum varies continuously from the longest wavelengths (the reddest colors) to the shortest wavelengths (the deepest violet colors) our eyes can detect. Wavelengths near 655 nm are perceived as red. Those near 515 nm are green and those near 475 nm are blue. Calculate the frequency of light (in Hz) with a wavelength of 655 nm, 515 nm, and 475 nm. HINT (a) 655 nm (b) 515 nm (c) 475 nm Hz Hz Hz

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?

An AM radio transmitter broadcasts 54.0 kW of power uniformly in all directions. (a) Assuming all of the radio waves that strike the ground are completely absorbed, and that there is no absorption by the atmosphere or other objects, what is the intensity (in W/m2) 26.0 km away? (Hint: Half the power will be spread over the area of a hemisphere.) W/m2 (b) What is the maximum electric field strength (in V/m) at this distance? V/m