Anemometer beam exits reflect, or backscatter, the light back into a detector, where it is measured relative to the original laser beam. When the particles are in great motion, they produce a Doppler shift for measuring wind speed in the laser light, which is used to calculate the speed of the particles, and therefore the air around the anemometer. Ultrasonic anemometers, first developed in the 1950s, use ultrasonic sound waves to measure wind velocity. They measure wind speed based on the time of flight of sonic pulses between pairs of transducers. Measurements from pairs of transducers can be combined to yield
What Does the K Stand For? sitcom". Writing in "The Guardian" in February 2015, Priya Elan judged that, "Standup comedian Stephen K Amos's jaunty sitcom "What Does The K Stand For?" (Radio 4) reaches the end of its second series with possibly the best episode yet. With shades of Chris Rock's "Everybody Hates Chris", Amos takes us back to his 80s childhood, growing up gay and black in a dysfunctional household". However, he added, "Playing it broad by mixing farce with double entendres, the sitcom is slightly uneven: although the family are drawn with wit and sympathy, minor characters like the actress turned teacher Miss Bliss