hey guys, could you expalin to me what the difference between angular and centrpietal accelleration is? all i rcan think of is that centripetal accleration is directed towards the centre :S im sure theres more lol
thanks!
2007-03-16 16:13:52 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Physics
You're correct on centripetal acceleration. Angular acceleration is the rate of change of angular velocity, or the second rate of change of an angle about a center. Multiplied by some radius r it yields tangential acceleration.
2007-03-16 16:22:22 · answer #1 · answered by Helmut 7 · 0⤊ 0⤋
Actually, the two concepts are not really related enough that you can "describe the differences." As far as I can remember from this past year of physics, angular acceleration is the analog of linear acceleration - it's the change in angular speed over a time interval. Angular speed is the change in a certain angle over an interval; for example, suppose you have an ant moving around the edge of a record. Let's say the record has a circumference of 1 m and the ant makes a full circle every 1 min; then the ant's LINEAR speed would be 1 m/min. BUT the ant also passes through 360 degrees, or 2*pi radians (around the record) every second - so its ANGULAR speed would be 2*pi radians/min.
Angular quantities like angular position (you know this quite well as the ANGLE, measured in degrees or radians), angular velocity, and angular acceleration are just the analogs of their linear counterparts.
Centripetal acceleration, on the other hand, is equal to v^2/r, where v is the LINEAR speed. Suppose you swing a ball on a string in a circle above your head, at constant speed. The ball may seem like it's moving at constant speed to you, but it is in fact undergoing CONSTANT ACCELERATION, because - what is the definition of acceleration? CHANGE IN VELOCITY! And velocity has a DIRECTIONAL component as well as a magnitude - so if you're changing direction, you're changing velocity and you've got acceleration! Of course, when you move in a circle, you're constantly changing direction. This acceleration vector is all pointing towards the center - the ball is accelerating towards the CENTER; it's just its speed that makes it move in a circle - and the magnitude of that acceleration, called centripetal acceleration, is v^2/r.
This is kind of incoherent... hope it helped!
2007-03-16 23:27:14 · answer #2 · answered by dac2chari 3 · 0⤊ 0⤋
Velocity: m/s v=2piR/t
Angular velocity: degrees/s. 2piR=360 degrees
Centripetal acceleration is in m/s^2 (v2/R or 2piv/T)
Angular acceleration: degrees/s^2
2007-03-16 23:26:43 · answer #3 · answered by Rob S 3 · 0⤊ 0⤋