Calculate Path Length of Wheel Rotation at 30°, Rad, Rev

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To calculate the path length of a wheel with a radius of 3.7 m rotated through 30°, 30 rad, and 30 rev, the formula s = θ * r is used, where θ is the angular displacement in radians. The discussion clarifies that the problem focuses on understanding angular displacement rather than involving angular velocity or acceleration. The initial confusion stemmed from misapplying kinematic equations, which are unnecessary for this calculation. After clarification, the correct approach was confirmed, emphasizing the importance of recognizing different expressions of angular displacement. This understanding is crucial for solving similar problems in the future.
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A wheel has a radius of 3.7 m. How far (path length) does a point on the circumference travel if the wheel is rotated through angles of 30°, 30 rad, and 30 rev, respectively?

30° m
30 rad m
30 rev m

I really need help on this. I don't even understand what I am suppose to do because I don't really understand the question and from what the teacher told us had nothing or in anyway how to solve an equation like this.

for the first equation i tried using this
deltaTheta = w_initial*t + 1/2alphat^2 but then i realize i don't know what alpha or t is. so that's when i thought w_initial is 0 so

deltaTheta = 1/2alpha*t^2 then i got this s = theta*r which will give me time in second but not sure.

any help would be great and very helpful to my studying.
 
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This question has nothing to do with angular velocity or acceleration. It is just to make sure you understand the various ways of expressing angular displacement.
 
so to find the answer would i do this

s = theta*r
Vi = W*r
a = alpha*r

finding that using kinetic formula to get distance? deltax = Vit + 1/2at^2 and v^2 = vi^2 + 2adeltaX
 
BunDa4Th said:
so to find the answer would i do this

s = theta*r
Vi = W*r
a = alpha*r

finding that using kinetic formula to get distance? deltax = Vit + 1/2at^2 and v^2 = vi^2 + 2adeltaX
I repeat...
OlderDan said:
This question has nothing to do with angular velocity or acceleration. It is just to make sure you understand the various ways of expressing angular displacement.
You have used one of the ways correctly.
 
oh okay i got it now thanks for clearing that up.
 
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