The process of deriving the angular velocity direction of uniform circular motion.

Uniform circular motion.

1.Linear velocity v=s t=2 r t 2Angular velocity = t=2 t=2 f

3.Centripetal acceleration a=v2 r= 2r=(2 t)2r 4Centripetal force f centr=mv2 r=m 2r=m(2 t)2rr

5.Cycle vs. frequency t=1 f 6The relationship between angular velocity and linear velocity v= r

7.Angular velocity vs. rotational speed =2 n (where frequency has the same meaning as rotational speed).

8.Main physical quantities and units: Arc length (s): m (m) angle ( ) radian (rad) frequency (f): hertz (hz).

Cycle (t): seconds (s) Rotational speed (n): r s Radius (r): meters (m) Linear velocity (v): m s

Angular velocity ( ) rad s centripetal acceleration: m s2

Note: (1) The centripetal force can be provided by a specific force, or by the resultant force, or by the component force, and the direction is always perpendicular to the direction of velocity. (2) The centripetal force of an object moving in a circular motion with uniform velocity is equal to the resultant force, and the centripetal force only changes the direction of the velocity, but does not change the magnitude of the velocity, so the kinetic energy of the object remains the same, but the momentum keeps changing.

This is not derivative, it is defined according to the right-hand rule. Stretching out the right hand, the thumb is perpendicular to the four fingers, when an object is moving in a circle, use the four fingers of the right hand to bend the direction of the object's movement, then the thumb is pointing in the direction of w.

We know. The relationship between the linear quantity and the angular quantity of circular motion is v=rw, because these three physical quantities are all directional quantities, v is the velocity, the direction is tangential along the arc, r is the position vector, the magnitude is the radius of the circular motion, the direction is pointing from the center of the circle to the object, w angular velocity. Since v=rw is satisfied, all three are vectors, so mathematically, these three quantities satisfy the relation of cross product.

Since the direction of w can be determined by the right-hand rule, the vector relation of the three can be obtained v=r x w (in this formula, v r w is the vector with an arrow on the head).

This direction should not be deduced, right? It seems to be directly defined: the right-hand spiral rule.

The tangential acceleration may not change, but the normal acceleration must change. Because of the uniform circular motion, the tangential acceleration is zero, and the acceleration is constant, but the direction changes greatly at all times. In a circular motion with variable speed, the tangential acceleration is constant, but the direction changes, and the normal acceleration value also changes in the direction.

The motion of a particle in a circle with a radius of r centered on a certain point, that is, the movement of a particle whose trajectory is a circumference is called "circular motion". It is one of the most common curvilinear movements. For example, the rotor of the motor, the wheel, the pulley, etc., all move in a circle.

Circular motion is divided into, uniform circular motion and variable speed circular motion (e.g., rope rod rotating ball in vertical plane, cone pendulum motion in vertical plane). In circular motion, the most common and simplest is uniform circular motion (because velocity is a vector quantity, uniform circular motion actually refers to uniform circular motion).

Summary. Uniform acceleration circular motion is a uniform rate curve motion with no change in radius, angular velocity, period, and rotational speed, and constant linear velocity, centripetal acceleration, and direction pointing to the center of the circle.

Is uniform angular acceleration of circular motion equal to uniform acceleration of circular motion? Hold on. Good.

Hello, regarding your question, I found the following answer. is equal. The relationship between its macro and the uniform velocity of the circular motion is to describe the circular motion from different physical quantities.

Because in a uniform circular motion v = rv = at, it is obvious that the masking angle acceleration = t, r=a

Don't you see the problem clearly.

Not a uniform circular motion. Good. Well.

Not equal. Uniform acceleration circumferential movement is a uniform velocity curve with the radius of the sock wheel, angular velocity, period, and rotational speed unchanged, linear velocity, centripetal acceleration and direction pointing to the center of the circle.

Uniform angular acceleration circular motion is the circular motion with constant angular acceleration, that is, the rate of change of angular velocity is a certain value Uniform circular motion is the circular motion with constant angular velocity, and the ephemeral rate of change of angular velocity is constant zero.

The two are not equal.

Thank you, teacher. Thank you so much.

The use of counter-evidence can be illustrated:

Assuming that the direction of acceleration in a uniform circular motion is not directed to the center of the circle, the vector of acceleration can be delimited and decomposed into the sum of the acceleration component in the tangential direction and the acceleration in the direction of the center of the circle.

If there is an acceleration component in the tangent direction, then the velocity in the tangent direction is changing, which does not conform to the motion law of uniform circular motion, so there is no acceleration component in the tangent direction, only acceleration in the direction of the center of the circle.

Uniform circular motion 1Linear velocity v=s shed envy manuscript t=2 r t 2Angular velocity = t=2 t=2 f 3

Centripetal acceleration a=v2 r= 2r=(2 t)2r 4Centripetal force f center = mv2 piexin r = m 2r = m(2 t)2r 5Cycle vs. frequency t=1 f 6

Angular velocity vs. linear velocity v= r 7The relationship between angular velocity and the filial velocity of the chain =2....

Summary. Hello, when the angle between the direction of the combined external force and the direction of velocity of the object is 90 degrees, the object will move in a uniform circular motion with constant velocity.

Hello, when the angle between the direction of the combined external force and the direction of velocity of the object is 90 degrees, the object will move in a uniform circular motion with constant velocity.

Oh ok, thanks

The reason why the angle between the combined external force and the velocity direction of the object in a circular motion is 90° is as follows: the direction of the combined external force is 90° with the direction of velocity, and the component of the combined external force in the direction of velocity is zero, that is, the magnitude of the velocity does not change, and the direction of velocity changes due to the external force, and the object moves in a uniform circular motion.