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For projectiles in unpowered flight, its velocity is highest at leaving the muzzle and drops off steadily because of air resistance.Projectiles traveling less than the speed of sound (about 340 m/s (1,100 ft/s) in dry air at sea level) are subsonic, while those traveling faster are supersonic and thus can travel a substantial distance and even hit a target before a nearby observer hears the ...
Here the speed is displayed both in knots (kn) and miles per hour (mph). The true airspeed ( TAS ; also KTAS , for knots true airspeed ) of an aircraft is the speed of the aircraft relative to the air mass through which it is flying.
This schlieren image of a bullet travelling in free-flight demonstrates the air-pressure dynamics surrounding the bullet. External ballistics or exterior ballistics is the part of ballistics that deals with the behavior of a projectile in flight. The projectile may be powered or un-powered, guided or unguided, spin or fin stabilized, flying ...
Detonation velocity is the speed with which the detonation shock wave travels through the explosive. It is a key, directly measurable indicator of explosive performance, but depends on density which must always be specified, and may be too low if the test charge diameter is not large enough.
Bullets used in many cartridges are fired at muzzle velocities faster than the speed of sound [10] [11] —about 343 metres per second (1,130 ft/s) in dry air at 20 °C (68 °F)—and thus can travel substantial distances to their targets before any nearby observers hear the sound of the shots.
Sporting bullets, with a calibre d ranging from 4.4 to 12.7 millimetres (0.172 to 0.50 in), have C b in the range 0.12 lb/in 2 to slightly over 1.00 lb/in 2 (84 kg/m 2 to 703 kg/m 2). Those bullets with the higher BCs are the most aerodynamic, and those with low BCs are the least.
For example: the energy of TNT is 4.6 MJ/kg, and the energy of a kinetic kill vehicle with a closing speed of 10 km/s (22,000 mph) is 50 MJ/kg. For comparison, 50 MJ is equivalent to the kinetic energy of a school bus weighing 5 metric tons, traveling at 509 km/h (316 mph; 141 m/s).
We can now use momentum conservation for the bullet-pendulum system to get the speed of the bullet, , before it struck the pendulum. Equating the momentum of the bullet before it impacts the pendulum to that of the bullet-pendulum system as soon as the bullet strikes the pendulum (and using v 1 = 2 ⋅ g ⋅ h {\displaystyle v_{1}={\sqrt {2 ...