Draw two perpendicular lines from the tails of the velocity vectors. Now draw a line joining their heads which intersects the perpendicular line. That point of intersection is the ICOR. Here point C is the Instantaneous centre of rotation.

So, when the acceleration is 0 the velocity is -1. v(0) just gives you the object’s initial velocity, which is 3 units/s. To find when the velocity is zero you want to find all t such that 0=t2−4t+3. There should be two solutions, t1,t2 as v(t) is a quadratic.

Point M is the instantaneous center of rotation for a rigid body rotating with angular velocity ⃗ω , and Q is any point on the body. By definition the instantaneous center has ⃗vM=0 v → M = 0 , so the velocity formula #rkg-er gives: ⃗vQ=⃗vM+⃗ω×⃗rMQ=⃗ω×⃗rMQ.

Explanation: The number of pairs of links or the number of instantaneous centres is the number of combinations of n links taken two at a time. Mathematically, number of instantaneous centres, N = n(n – 1)/2.

(Kennedy’s theorem) For n bodies moving with respect to one another there are n(n-1)/2 instant centers. KENNEDY’S THEOREM. If three bodies have plane motion relative to one another, then there are three instant centers, and the three instant centers all lie on the same line.

The center of rotation is a point about which a plane figure rotates. This point does not move during the rotation.

The angle of rotation is the amount of rotation and is the angular analog of distance. The angle of rotation Δθ is the arc length divided by the radius of curvature. 1 revolution = 2πrad = 360°.

Rule. When we rotate a figure of 180 degrees about the origin either in the clockwise or counterclockwise direction, each point of the given figure has to be changed from (x, y) to (-x, -y) and graph the rotated figure.

The 180 degree rotation acts like both a horizontal (y-axis) and vertical (x-axis) reflection in one action. The reflection is the same as rotating the figure 180 degrees.

do a 180. 1. Literally, to begin moving in the opposite direction. (If one physically turns 180 degrees, one will then be facing the opposite direction.)

A half-rotation is 180 degrees, which around the same central axis would place you in a position facing opposite to where you faced originally.

From Longman Dictionary of Contemporary English do a 180informal a) to turn around so that you are then facing in the opposite direction, for example on a bicycle or a skateboard b) to completely change your attitude to something or your plans for something → U-turn They have done a 180 on the issue of immigration.