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an increase of 240 dB, because the units increase by factors of 10 3 and 10 9 respectively, so: + = (The constants differ in the second decimal digit when the speed of light is approximated by 300 000 km/s.
Attenuation. In physics, attenuation (in some contexts, extinction) is the gradual loss of flux intensity through a medium. For instance, dark glasses attenuate sunlight, lead attenuates X-rays, and water and air attenuate both light and sound at variable attenuation rates. Hearing protectors help reduce acoustic flux from flowing into the ears ...
The crossover was set to diverging with a 100 km/h (62 mph) speed limit but the LZB system displayed a 180 km/h (112 mph) limit. The driver of ICE 1652 recognized the diverging signal and managed to slow down to 170 km/h (106 mph) before the crossing and the train did not derail.
Speed limit 80 or 90 km/h: The speed trap uses a 1000 Hz inductor and is located at the distant signal. If train passes the speed trap with more than signaled speed + 15 km/h (i.e., 95 or 105 km/h), it will capture a 1000 Hz influence, which the train driver has to acknowledge (and brake to 55/70/85 km/h). Speed limit 100 to 140 km/h: The speed ...
The decibel originates from methods used to quantify signal loss in telegraph and telephone circuits. Until the mid-1920s, the unit for loss was miles of standard cable (MSC). 1 MSC corresponded to the loss of power over one mile (approximately 1.6 km) of standard telephone cable at a frequency of 5000 radians per second (795.8 Hz), and matched closely the smallest attenuation detectable to a ...
Indicates that a signal at danger may be passed when wrong line working is in force. If the signal guards points/switches the speed limit is 40 km/h; otherwise, the limit is 100 km/h to the next station. As with other 'wrong line operation' signals, this is only used where wrong line operation is frequent.
Speeds of 950 km/h (590 mph) are reported to have been attained in a shallow dive 20° to 30° from the horizontal. No vertical dives were made. At speeds of 950 to 1,000 km/h (590 to 620 mph) the air flow around the aircraft reaches the speed of sound, and it is reported that the control surfaces no longer affect the direction of flight.
Passenger trains are limited to 59 mph (95 km/h) and freight trains to 49 mph (79 km/h) on track without block signal systems. (See dark territory.) Trains without "an automatic cab signal, automatic train stop or automatic train control system "may not exceed 79 mph (127 km/h)." The order was issued in 1947 (effective December 31, 1951) by the ...