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The speed at which light propagates through transparent materials, such as glass or air, is less than c; similarly, the speed of electromagnetic waves in wire cables is slower than c. The ratio between c and the speed v at which light travels in a material is called the refractive index n of the material (n = c / v ).
The most noticeable aspect of lightning and thunder is that the lightning is seen before the thunder is heard. This is a consequence of the speed of light being much greater than the speed of sound. The speed of sound in dry air is approximately 343 m/s (1,130 ft/s) or 1,236 km/h (768 mph) at 20 °C (68 °F; 293 K). [19]
Positive lightning is less common than negative lightning and on average makes up less than 5% of all lightning strikes. [ 10 ] A bolt from the blue lightning strike which appears to initiate from the clear, but [ clarification needed ] the turbulent sky above the anvil cloud and drive a bolt of plasma through the cloud directly to the ground.
Lightning currents have a very fast rise time, on the order of 40 kA per microsecond. Hence, although lightning is a form of direct current, conductors of such currents exhibit marked skin effect as with an alternating current, causing most of the currents to flow through the outer surface of the conductor. [32]
The Earth is struck by lightning nearly 20 million times each year, and bolts of lightning can travel as much as 10 to 12 miles from a thunderstorm, instantly heating the air to 50,000 degrees ...
A return stroke, cloud-to-ground lightning strike during a thunderstorm. Cloud-to-ground lightning frequently occurs within the phenomena of thunderstorms and have numerous hazards towards landscapes and populations. One of the more significant hazards lightning can pose is the wildfires they are capable of igniting. [54]
The speed at which energy or signals travel down a cable is actually the speed of the electromagnetic wave traveling along (guided by) the cable. I.e., a cable is a form of a waveguide. The propagation of the wave is affected by the interaction with the material(s) in and surrounding the cable, caused by the presence of electric charge carriers ...
Speed of International Space Station and typical speed of other satellites such as the Space Shuttle in low Earth orbit. 7,777: 28,000: 17,400: 2.594 × 10 −5: Speed of propagation of the explosion in a detonating cord. 10 4: 10,600 38,160 23,713.65 0.00004 Speed of propagation of the explosion of Octanitrocubane (ONC). 11,107: 39,985.2: ...