Concept explainers
To Define:
The SI unit radian and explain when it is appropriate to include and when the unit should be dropped.
Explanation of Solution
Introduction:
A unit of measurement of angles equal to approximately 57.3 °, equivalent to the angle subdued at the center of a circle by an arc equal to the radius in length.
The relationship between speed and radius of the rotation of an object can be rewritten as
A distance r from the point of rotation moving at v for an object or piece of an object. Since
In measuring certain rotational speeds, we use "rotations per minute "not "degrees per second ".
When a satellite orbits the Earth, we see its speed in "miles per hour "rather than" degrees per hour". Now divide by the distance to the satellite and the orbital speed is achieved in radians per hour.
The radian is a dimensionless unit that may be dropped, although the plane-angle is not an official measure (SI) and radian can be dropped.
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Chapter 8 Solutions
College Physics Volume 2
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