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Need help with trigs :p (1 Viewer)

joto

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The question is:
A) A wheel on a fixed axle is rotating at 200 revolution per minute. Convert this angular velocity into radians per second, giving your answer to the nearest whole number.
B) If the radius of the wheel is 0.3 metres, how far, to the nearest metre, will a point on the outside edge of the wheel travel in one second.

It would be most helpful if any of you can answer my question, got stuck in this question for awhile TT
thank you
 

bleakarcher

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a) 200 revs/min=200/60 revs/s=10/3 revs/s
Now, angular velocity=2pi*10/3 radians/s=20pi/3 radians/s
b) Per second the wheel did 10/3 revolutions meaning the point of the outside edge of the wheel will travel 10/3 times the circumference of the wheel.
So distance travelled=(10/3)*2pi*0.3=2pi metres.
 

joto

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a) 200 revs/min=200/60 revs/s=10/3 revs/s
Now, angular velocity=2pi*10/3 radians/s=20pi/3 radians/s
b) Per second the wheel did 10/3 revolutions meaning the point of the outside edge of the wheel will travel 10/3 times the circumference of the wheel.
So distance travelled=(10/3)*2pi*0.3=2pi metres.
um.....can u explain what u did??
i don think i get it
 

IamBread

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um.....can u explain what u did??
i don think i get it
a)200 revs/min means it goes around in a circle, 200 times every minute. As and 1 minutes = 60 seconds, we get

b)Now we have the angular velocity, , we can find the velocity and the circumference. Using the formula , we get


 

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