Angular Position, Velocity and Acceleration. AP Physics C Mrs. Coyle. Rigid Body. -An object or system of particles in which distances between the particles are constant. There is no deformity in the object. - Real object have some deformity. Translation , Rotation , Rolling.
Angular Position, Velocity and Acceleration
AP Physics C
-An object or system of particles in which
distances between the particles are constant. There is no deformity in the object.
- Real object have some deformity.
O is the point through which the axis of rotation passes.
(Final Angle-Initial Angle)
In this figure qo=0
q= s s=qr
q in radians
1 rad = = 57.3°
q [rad] = [degrees]
SI unit : rad/sec
or 1/sec or sec-1
Wrap the four fingers in the direction of rotation. The thumb shows the direction
of the angular velocity vector.
+ angular velocity for counterclockwise rotation.
- angular velocity for clockwise rotation.
The angular position of a swinging door is described by θ= 5+10t+2t2, θ is in radians and t is in sec. Detremine the angular position, angular speed and angular acceleration of the door a)at t=0 and b) at t=3s.
Ans: a)5 rad, 10rad/s, 4 rad/s2 , b)53 rad, 22rad/s, 4 rad/s2
A centrifuge in a medical lab rotates at an angular speed of 3600 rev/min. When switched off, it rotates 50 times before coming to rest. Find the constant angular acceleration of the centrifuge.
Ans: α= -2.26x10 2rad/s2
A dog is running on the ground just outside a stationary merry-go-round with a constant angular speed of 0.750 rad/s. The dog sees a bone resting on the edge of the merry-go-round one third of a revolution in front of him. At the instant the dog sees the bone (t=0) the merry-go-round begins to move in the direction the dog is running with a constant angular acceleration of 0.015 rad/s2 .
a)At what time will the dog reach the bone? (A:2.88s)
b)If the dog runs past the bone how long after t=0 does the dog reach the bone a second time?(Ans:12.8s)