The term business cycle refers to economy-wide fluctuations in production, trade, and general economic activity. Identify features of the economic business cycle. Business cycles are identified as having four distinct phases: expansion, peak, contraction, and trough. An expansion is characterized by increasing employment, economic growth, and upward pressure on prices.
The speed of light in a given material is related to a quantity called the index of refraction, n, which is defined as the ratio of the speed of light in vacuum to the speed of light in the medium: index of refraction: n = c / v.When light travels from one medium to another, the speed changes, as does the wavelength.efraction. When we talk about the speed of light, we're usually talking about the speed of light in a vacuum, which is 3.00 x 10 8 m/s. When light travels through something else, such as glass, diamond, or plastic, it travels at a different speed.
Main article: Speed of light. The speed of light in a vacuum is defined to be exactly 299,792,458 m/s (approx. 186,282 miles per second). The fixed value of the speed of light in SI units results from the fact that the metre is now defined in terms of the speed of light.