Question

Suppose that a disk rotates through two revolutions in 5 seconds.

a) what is its displacement in radians in this time?

b)what is its average rational velocity in rad/s?

Answer 1

To solve this problem you have to know about Rotational cinematic

Step 1.

Definition:

Definition: A rigid body is one that does not change shape or volume while moving. These bodies can be considered as a conglomerate of particles located in fixed positions relative to each other.

It is said that a rigid body is animated by a movement of rotation around a fixed axis when all its points describe circular paths centered on said axis and contained in planes normal to it.

The rotation axis may pass through the body or be external thereto; in the first case, the solid points that are on the shaft remain at rest while the other points describe circles around the axis; in the second case, all the solid points are in circular motion around the axis outside of the solid. In any case, the speed v of a solid point P is tangent to the circumference described and, in a given time, will have a much higher modulus the greater the distance from the point to the rotation axis.

Step 2.

a) what is its displacement in radians in this time?

, if the disk do 12.56 rad in a one second, how much will make in 5 s

b)what is its average rational velocity in rad/s?

If you have any question please let me know in the comments