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Physics: does angular velocity have direction?
Angular velocity tuning: the arc that connects the radius of the moving particle and the center of the circle in unit time is called "angular velocity". So there is direction, but the direction is constantly changing
There are three symmetrically distributed radii on a disk, which rotate around the center of the disk at a uniform speed. The flash lamp is used to illuminate the disk every 1 / 30s. In order to make the disk look motionless, what conditions should the angular velocity meet? In order to make the disk look inverted, what conditions should the angular velocity meet?
30n.pai
15 n. Pai, n is odd
The angular velocity of the hour, minute and second hands on a watch
A: the ratio of the angular velocity of minute hand and hour hand is 1:60
The ratio of the angular velocity of the minute hand to the hour hand is 1:12
C the ratio of the angular velocity of the second hand to the minute hand is 1:12
D the ratio of angular velocity of second hand to minute hand is 1:60
The answer is B, D
The method I see is calculated with w = radian / T, but I use w = 2 π / T to work out why it is 12:1 and 60:1. Can't I use this method to solve it!
Isn't w = radian / t the same as w = 2 π / T?
Obviously is the second hand > minute hand > hour hand, I think the answer is wrong
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