Meter wavelength expressed

The gamma rays emitted by °Co are used in radiation treatment of cancer. They have a frequency of 2.83 X 10 ° s. Calculate their wavelength, expressing your answer in meters and in angstroms. 

This is not really very complicated and it applies equally well to water waves or electromagnetic radiation. What is almost needlessly complicated is the variety of units commonly used to express k and v for electromagnetic radiation. One problem is tradition, the other is the desire to avoid very large or very small numbers. Thus, as Figure 9-7 shows, we may be interested in electromagnetic wavelengths that differ by as much as a factor of 1016. Because the velocity of electromagnetic radiation in a vacuum is constant at 3 X 108 meters sec-1, the frequencies will differ by the same factor. 

Strategy In each case, we use the de Broglie relation. The mass of a proton is given in Table B.l, and the speed of light is given inside the back cover. Expect the macroscopic object, the marble, to have a very short wavelength. Remember to express all quantities in kilograms, meters, and seconds, and use 1 J = 1 kg-m2-s-2. 

KzX is usually expressed per meter and depends on wavelength and water composition. Typically, ultraviolet radiation penetrates less deeply than visible radiation. Attenuation coefficients vary over many orders of magnitude in natural waters, with the highest values (least light penetration) in inland water bodies and the lowest values (highest penetration) in open seawater. The photic zone for solar ultraviolet radiation, which is very important for halocarbon photoreactions, ranges from tens of meters in the open ocean and clear lakes to only a few centimeters in some inland wetlands. The spectral properties of water bodies are linked to water composition. Baker and Smith (20) developed algorithms that relate K,k to certain parameters such as chlorophyll a concentrations. 

Wavelength is usually expressed in units of meters, centimeters, or nanometers, and frequency is measured in hertz (Hz), where... 

The spectral radiant flux density, F(X), is the radiant flux density per unit wavelength interval, expressed in watts per square meter per nanometer (W m 2 nm ). Equivalently, when considering radiation incident upon a surface, the spectral irradiance, E(X), is expressed as W m-2 nm 1. 

The wavelength (represented by X, the Greek letter lambda) is the shortest distance between equivalent points on a continuous wave. For example, in Figure 5.2b, the wavelength is measured from crest to crest or from trough to trough. Wavelength is usually expressed in meters, centimeters, or nanometers (1 nm = 1 x 10 m). 

Spectral Irradiance - The monochromatic irradiance of a surface per unit bandwidth at a particular wavelength, usually expressed in Watts per square meter-nanometer bandwidth. 

This was followed hy contrihuflons of Joseph von Fraunhofer, who used a telescope and thereby created the first spectrometer, as a tool for seeing the different components of radiation. In 1868, Angstrom (Figure 9.4b) measured 1,000 Fraunhofer lines and expressed their wavelength using the unit 0.0000000001 meters (10 ° m), which is now called 1 A after his name, and serves to gauge the dimension of atomic and molecular size. 

All electromagnetic radiation travels through a vacuum at the same velocity. This velocity (c), called the velocity of light, is 2.99792458 X 10 m s and relates to wavelength and frequency as t = Xv. The wavelengths of electromagnetic radiation are expressed either in meters (m), millimeters (1 mm = 10 m), micrometers (1 m = 10 m), or nanometers (1 nm = 10 m). [An older term for micrometer is micron (abbreviated x) and an older term for nanometer is millimicroni ... 

Radar reflectivity factor (Ze) Product of the number of hydrometeors per cubic meter and the average sixth power of their diameters expressed as millimeters conventionally presented in units of dBZ, defined as 10 login For long-wavelength weather radar, Ze is a measure of the reflectivity of hydrometeors. 

Wavelength is the distance between any two consecutive identical points on the wave. Wavelength is given the symbol A (Greek lowercase lambda) and is usually expressed in the SI base unit of meters. Other derived units commonly used to express wavelength are given in Table 11.2. 

Wavelength, X (meters), is the distance between successive pressure (stress) peaks of the soimd wave, and is the spatial periodicity of the wave. Frequency and wavelength are defined for a sinusoidal, harmonic (single-frequency) sound wave. More complicated, transient sound signals can be expressed as a superposition of harmonic waves with different frequencies. 

As shown above, wavenumbers are easily converted to wavelength values. The reciprocal of v and conversion of centimeters to wavelength units are all that is required (this is particularly handy because much early IR data were recorded linearly in wavelength). The wavelength unit employed in most of these spectra was the micron, g (1 X 10 cm). The micron has been replaced by a unit expressed in meters, the micrometer, gm (1 gm = 1 X 10 m). 

Table 12.2 Common Units Used to Express Wavelength (A) Relation Unit to Meter ...

Wavelength is usually expressed in the SI base unit of meters. Other derived units commonly used to express wavelength are given in Table 12.2. 

---