Electromagnetic Spectrum Activity - X-rays
Resources
- NASA EM Spectrum Information Pages X-rays
- Discovery Education EM Spectrum
- List of SI (metric) prefixes . e.g. nano, milli, mega, tera.
X-rays are a band of the EM spectrum that many of us have experienced in a medical environment. X-rays have more energy than ultraviolet light but less than gamma rays. X-rays are ionizing radiation. Ionizing radiation has enough energy to tear electrons away from their atoms. The atoms are now 'ions'. These ions can cause unwanted chemical reactions in a material or organism.
With shorter wavelengths it is more common to refer to the wave's wavelength rather than its frequency. X-rays covers the range from 0.01 to 10 nm (nm = nanometers = 1x10-9). The frequency would be expressed in Phz (Petahertz) or Ehz (exahertz) . A high frequency wave has a short wavelength. The relationship is defined as:
- Variables: λ=wavelength (m) v = speed of light (3 x 108 m/s) f = frequency (Hz). Note EHz = 1 x 1018 Hz
- Formula: λ = v ÷ f
- Example: λ = 3 x 108 m/s ÷ 3 EHz = 0.1 nm
In nature, X-rays are made by objects in space such as stars, supernova and black holes. Humans make x-rays by using high voltage (up to 150,000 volts) to slam electrons into a metal, often titanium. The movement of electrons in the target metal generates the x-rays. The typical use of x-rays is to look through optically opaque objects, such as you! The x-rays travel trough an object and strike a photographic film or sensor. The strength of the image generated is related to the density of the object being x-rayed.
Another use of x-rays was made famous by the discover of the structure of DNA. Rosalind Franklin used x-ray crystallography to determine the double helix structure of DNA.
EM Spectrum Data Table
| Name | Wavelength Range | Wavelength (comparative size) |
Frequency Range | Energy ionizing/ med / lo |
Sources | Uses |
|---|---|---|---|---|---|---|
| X-rays |
Waves Glossary
- Electromagnetic waves
- Radiation consisting of waves of energy sent through space and matter associated with electric and magnetic fields resulting from the acceleration of an electric charge (light, x-rays, microwaves, gamma rays, etc.). 3.9
- Frequency
- The number of back-and-forth cycles per second, in a wave or wave-like process. 3.5
- Period
- The time for one wavelength to pass a point. The time for a wave to travel the distance of one wavelength. P= 1/frequency. 3.5
- Wave
- A rhythmic disturbance that transfers energy from place to place. 3.5
- Wavelength
- The distance measured from crest to crest of one complete wave or cycle. 3.5