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Chainline on a fixed-gear bicycle. The chainline is the angle of a bicycle chain relative to the centerline of the bicycle frame. [1] A bicycle is said to have a perfect chainline if the chain is parallel to the centerline of the frame, which means that the rear sprocket is directly behind the front chainring. [1]
From a mechanical viewpoint, up to 99% of the mechanical energy delivered by the rider into the pedals is transmitted to the wheels (clean, lubricated new chain at 400 W), although the use of gearing mechanisms reduces this by 1–7% (clean, well-lubricated derailleurs and a straight chainline), 4–12% (chain with 3-speed hubs), or 10–20% (shaft drive with 3-speed hubs).
Bicycle chains Roller chain and sprocket. A bicycle chain is a roller chain that transfers power from the pedals to the drive-wheel of a bicycle, thus propelling it.Most bicycle chains are made from plain carbon or alloy steel, but some are nickel-plated to prevent rust, or simply for aesthetics.
Cutting speed may be defined as the rate at the workpiece surface, irrespective of the machining operation used. A cutting speed for mild steel of 100 ft/min is the same whether it is the speed of the cutter passing over the workpiece, such as in a turning operation, or the speed of the cutter moving past a workpiece, such as in a milling operation.
Signal velocity is usually equal to group velocity (the speed of a short "pulse" or of a wave-packet's middle or "envelope"). However, in a few special cases (e.g., media designed to amplify the front-most parts of a pulse and then attenuate the back section of the pulse), group velocity can exceed the speed of light in vacuum, while the signal ...
A sphere rotating around an axis. Points farther from the axis move faster, satisfying ω = v / r.. In physics, angular frequency (symbol ω), also called angular speed and angular rate, is a scalar measure of the angle rate (the angle per unit time) or the temporal rate of change of the phase argument of a sinusoidal waveform or sine function (for example, in oscillations and waves).
Authorities have yet to determine a reason for the collision. The American Airlines jet was carrying 60 passengers and four crew when it went down. Three soldiers were aboard the helicopter.
Brown was a proponent of fixed-gear, single-speed bicycles for ordinary street use. [26] Brown, with Galen Evans and Osman Isvan, developed a method to determine and compare bicycle gear ratios. For any combination of front chainring, rear cog, wheel size and crank length, his method results in a number that Brown terms the "gain ratio". [27]