Electromagnetic waves can form standing waves. In a standing wave pattern formed from microwaves, the distance between a node and an adjacent antinode is 0.65 cm. What is the microwave frequency?

Electromagnetic radiation having a 62.8 µm wavelength is classified as infrared radiation. What is its frequency? Hz

A certain electromagnetic wave has an average intensity of 6 x 104 W/m2. What is the average energy density of the wave? Highl 3 x 10-8 J/m³ 2 x 10-4 j/m³ O 6 x 104 J/m³

The ionosphere is the ionized part of the upper layer of the earth's atmosphere. The air molecules there are ionized by solar radiation. This layer of the atmosphere is a fairly good conductor, and radio waves are often "bounced" off the bottom of the ionosphere back toward the earth, in a process called skip or skywave propagation. Due to these properties, the space between the surface of the earth and the bottom of the ionosphere acts like a closed wave guide that will exhibit resonance for very low frequencies. Resonance excitations in the cavity are caused by lightning strikes, which hit the earth about 50 to 100 times a second. These low atmospheric resonance frequencies are known as Schumann resonances, named after the physicist Winfried Otto Schumann, who first calculated them in 1952. There are several Schumann frequencies that occur in the low frequency background, which ranges from 3 to 60 Hz. The highest intensity resonance mode (called the fundamental) occurs at 7.83 Hz.…

Electromagnetic radiation having a 14.5 µm wavelength is classified as infrared radiation. What is its frequency (in Hz)?

An electromagnetic wave with frequency 4.00 *10^14 Hz travels through vacuum in the positive direction of an x axis. The wave has its electric field oscillating parallel to the y axis, with an amplitude Em.At time t= 0, the electric field at point P on the x axis has a value of +Em/4 and is decreasing with time. What is the distance along the x axis from point P to the first point with E = 0 if we search in (a) the negative direction and (b) the positive direction of the x axis?

An electromagnetic wave of frequency 91.5 MHz travels in crown glass at a speed of 1.972x108 m/s. What is the wavelength of this wave while it is inside the glass?

At a certain geographic location, light intensity from the Sun is 900 J/(m² .s). This means that sunlight delivers 900 joules of energy to each square meter of ground in each second. Suppose solar panels are installed on the roof of a house to generate electricity from sunlight. The total area of the solar panels is 25 m². Calculate the maximum electric energy that can be generated per second: Unfortunately, solar panels are not 100% efficient at converting electromagnetic energy to electricity. Suppose the solar panels have an efficiency of 15%. This means that only 15% of the electromagnetic energy incident on the solar panels is converted to electricity, while the rest is reflected or converted to thermal energy. Given this efficiency, calculate the electric energy that can be generated per second:

Assume the mostly infrared radiation from a heat lamp acts like a continuous wave with wavelength 1.50 µm. (a) If the lamp's 205 W output is focused on a person's shoulder, over a circular area 24.0 cm in diameter, what is the intensity in W/m2? 2266.9 W/m2 (b) What is the peak electric field strength in kV/m? 0.924 X kV/m (c) Find the peak magnetic field strength in µT. 3.08 X µT (d) How long will it take in seconds to increase the temperature of the 3.80 kg shoulder by 2.00°C, assuming no other heat transfer and given specific heat is 3.47 x 103 J/(k • °C)? 128.64

The ionosphere is the ionized part of the upper layer of the earth's atmosphere. The air molecules there are ionized by solar radiation. This layer of the atmosphere is a fairly good conductor, and radio waves are often "bounced" off the bottom of the ionosphere back toward the earth, in a process called skip or skywave propagation. Due to these properties, the space between the surface of the earth and the bottom of the ionosphere acts like a closed wave guide that will exhibit resonance for very low frequencies. Resonance excitations in the cavity are caused by lightning strikes, which hit the earth about 50 to 100 times a second. These low atmospheric resonance frequencies are known as Schumann resonances, named after the physicist Winfried Otto Schumann, who first calculated them in 1952. There are several Schumann frequencies that occur in the low frequency background, which ranges from 3 to 60 Hz. The highest intensity resonance mode (called the fundamental) occurs at 7.83 Hz.…