wavelength waveÂ·length (wÄv'lÄngkth', -lÄngth') n. Symbol Î» The distance between one peak or crest of a wave of light, heat, or other energy and the next corresponding peak or crest.
Causes: Emphysema: The number one cause of emphysema is smoking. Other contributing factors in its development or exacerbation (increase in severity) include long-term exposure to other lung irritants, such as air pollution, chemical fumes, or dust.
In the vast majority of people, smoking is the cause of emphysema. Exactly how smoking destroys the air sac linings in the lungs isn't known. However, studies show that smokers are about six times more likely to develop emphysema than nonsmokers.