Electromagnetic Waves
1. Gamma-ray bursters are objects in the universe that emit pulses of
gamma rays with high energies. The frequency of the most energetic
bursts has been measured at around 3.0 x 10- Hz. What is the wave-
length of these gamma rays?
2. What is the wavelength range for the FM radio band (88 MHz-108 MHz)?
3. Shortwave radio is broadcast between 3.50 and 29.7 MHz. To what range
of wavelengths does this correspond? Why do you suppose this part of
the spectrum is called shortwave radio?
What is the frequency of an electromagnetic wave if it has a wavelength
of 10 km?
5. The portion of the visible spectrum that appears brightest to the human
eve is around 560 nm in wavelength, which corresponds to yellow-green.
What is the frequency of 560 nm light?
6. What is the frequency of highly energetic ultraviolet radiation that has a
wavelength of 125 nm?

Acoal-fired plant generates 600 mw of electric power. the plant uses 4.8 x 10^6 kg of coal each day, and the heat of combustion of coal is 3.3x 10^7 j/kg. the steam that drives the turbines is at a temperature of 300° c, and the exhaust water is at 37° c. (a) what is the overall efficiency of the plant for generating electric power? (b) how much thermal energy is exhausted each day? (c) what is the change in entropy of the universe for this heat engine? (d) using the same heat reservoirs, what is the maximum possible (carnot) efficiency for a heat engine?

Which of the following elements is in the same period as phosphorus? a. carbon c. nitrogen b. magnesium d. oxygen select the best answer from the choices provided a b c d

What elements are found in the inner and out core of the earth? the correct layers of earth's interior from the top to the center? what is the unwanted material that is removed from a mine called? how much stronger is an earthquake that registers 5 on the richter as opposed to 2? what occurs at a convergence plate boundary? the majority of the the earth's rock what is the most common element found in the earth's crust? what element is found in pyrite that contributes to acid mine drainage? why must mining companies post bond prior to permitting? how are bacteria being used in treating effluent from mines? what is a problem of acid mine drainage in rivers and soils? what do tectonic plates move on? why is gold smelting so damaging? how are artesian wells formed? where is dammed water colder than the river it flows into? what is one of the problems of uncontained aqueducts? what is the largest use of industrial water? underground sand and gravel formations that can store water? what type of water test measure acidity? which type of water test for cloudiness from suspended solids? what water test measures the amount of calcium and magnesium? these are all problems of coal power plants all of the following are advantages of riparian lands along rivers what type of water would be the warmest and have the least amount of dissolved oxygen? the zone of aeration is