How do I calculate the angular speed of a spinning object.?

A high-speed sander has a disk 4.10 cm in radius that rotates about its axis at a constant rate of 1280 revolutions per minute. Convert final answer into radians per secHow do I calculate the angular speed of a spinning object.?
1280 rev per min


=1280/60 rev per sec


since i rev=2pi rad


so total rad/sec=1280/60*2pi


=134.041rad/secHow do I calculate the angular speed of a spinning object.?
Angular velocity is just rpm divided by the radians in a circle... The ';speed'; of the disc is a different matter that is related to rpm and the circumference of the arc over which it operates.





The number of radians in a circle is about 360/57, or about 6. So, rpm is the number of 360 degree circles an object travels per minite. From here on, it is just simple math. Hope I helped...





Check the link...
Any circle, in radians, is 2pi. This rotates at 1280 rev/min.





1280 rev/min * min/60 sec = 21-1/3 rev/sec





21-1/3 rev/sec * 2pi rad/rev = (42-2/3)pi rad/sec





You don't need to know the radius of the disk unless you want to calculate the tangential velocity, which varies with the radius. It's just thrown in to fool you.





By the way, what temperature is it in the room in which the disk is rotating? :D
1 revolution is 2蟺 radians.


1280 revolutions is 1280*2蟺 radians = 2560蟺 radians





Sander does 2560蟺 radians in 60 seconds so in 1 second it does





2560蟺/60 radians/second


= 134.041 rad/s