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Contents: Acceleration | Speed
2. The space shuttle must accelerate to a speed higher than the orbital speed of 17-18,000 MPH to overcome air resistance, since the engines shut off before it reaches orbit. If you do the calculation the acceleration required is only 2 G, but since they are going almost straight up at the start you must add the 1G of gravity. It also accelerates faster in the first 2 minutes before the Solid Rocket Booster (SRB) seperation. See Affordable Space flight and Space Shuttle Launch Physics.
3. In 1954 Col. John P. Stapp rode a rocket sled to 632 mph in ~6 seconds and then came to a stop in 1.4 seconds. He experienced deceleration forces averaging 25 G's with a 40 G peak.
4. In a football 40 the timer starts his watch when the player starts running, so there's +.2 sec reaction time for the timer. The player is running whenever he wants to, he is not reacting to a gun, so there's another +.2 sec., so you may see claims of faster times by football players.
Deon Sanders reported time of 4.19, was probably the result of a bad timer.
5. In 2003 Michael Schumacher's raced his Formule 1 Ferrari F2003-GA against a Eurofighter Typhoon jet. The F1 car won at 600 meters (.37 mi.) but lost at 900. However, the plane only beat Schumacher by 0.2secs in the 900m dash - with a time of 13secs compared with the Ferrari's 13.2secs.
A formula 1 (F1) racecar's top speed is about the same as an Indy car, but it has better acceleration, braking and cornering. They can go 0 - 100 mph and back to zero in 4 secs. It can go from 185 mph to 0 in a little more than 2 seconds in a distance of 85 metres.
Gravity acceleration (G-Force): The force of gravity will cause an object dropped to accelerate. G = 9.81 (meters/sec)/sec = 32.2 ft./sec.2
Anything more than about 4 - 6 positive Gs will black people out, unless they are trained to fight it. Trained military pilots in G-suits can sustain up to 9 Gs. Higher G forces can be tollerated for fractions of a second. An average person could momentarily experience eight to ten Gs by plopping down onto the couch to watch TV. A woodpecker experiences 10 G of deceleration when its beak hits a tree.
x = a t2 / 2
v is velocity in ft/sec
x is distance in feet
a is acceleration in feet/sec2
t is time in sec
centrifugal force (radial or centripetal acceleration): Ar=V2/r Where: Ar=Radial Acceleration V=Velocity r=Radius of curveCentrifugal force is the force points out from the center, while centripetal force is the force that keeps the object in its circular path (gravity for an orbeting satelite).
Most cars tires will provide .7 - .8 Gs of radial acceleration before they break loose. Sports cars with racing tireswill get around 1 G.
* Note: There are a lot of web sites which state that a top fuel dragster will reach 200 MPH before half track and in order to do this the launch acceleration approaches 8Gs. it is actually 2-3 Gs
Solving the equations below for t2: t2 = v2/a2 and t2 = 2x/a equating both equations: v2/a2 = 2x/a solving for a: v2/(2x) = a2/a = a 200 MPH = 293.33 fps 1/8 mi. = 660 ft. a = 293.332/(2 * 660) = 65.18 feet/sec2 g = 65.18/32.2 = 2.02 Source: Richard IsaksonRoller Coasters:
Most coasters use a lift hill chain to start the ride; at the top of the hill, gravity takes over to accelerate the train. Momentum propels the trains through the ride and back to the station. Recently, coasters like Flight of Fear at Paramount's Kings Dominion and the Rock 'n' Roller Coaster at Disney-MGM Studios have used magnetic propulsion (linear induction motors - LIMs) to shoot the trains out of the loading stations. Cedar Point's Top Thrill Dragster and Great Adventure's Kingda Ka use a hydraulic launch system to rocket its trains out of the loading platform.
What makes a roller coaster ride exciting is the variety of G-forces, which include lateral G-forces going around a corner, weightlessness at the top of a hill, heaviness at the bottom and at the start ane end of loops.
The first looping coasters had circular loops. But dangerous G forces (up to 10 Gs) caused injuries such as whiplash. Anton Schwarzkopf and Werner Stengel developed the Clothoid loop with the intent of providing a smoother ride. They decreased the radius of the loop at the top and increased the radius at the bottom. This resulted in a smooth, wide curve at the bottom and a narrow curve at the top, where more centrifugal force was required to overcome gravity. This reduced forces to 3-4 Gs.
5. An antelope can maintain this speed for 4 mi. while the cheetah can only go for short distances.
6.Speeds for Indi cars and stock cars have been lowered with engine restrictions because of safety and cost considerations. Indy cars were around 228 MPH and Stock cars at super speedways are about 188 MPH in 2006. Both are 2.5 mile tracks. Banking at Indi is 9 degrees; at Daytone it's 31 degrees. Average speed for races are lower because of caution laps at lower speed.
Speed of sound in air:
6. Mach (M) = Speed of sound