Rotational Motion - Finding Linear Distance

AI Thread Summary
A 45.0 cm diameter wheel accelerates from 205 rpm to 385 rpm in 7.5 seconds, prompting a calculation of the distance traveled by a point on its edge. The user initially converted the RPM values to rad/s and calculated angular acceleration using the formula a=(w-v)/t. They attempted to find the angular displacement using w^2=v^2 + 2ah but encountered issues converting radians to meters. Ultimately, the user resolved the problem independently and expressed gratitude for any assistance. The discussion highlights the importance of showing calculations for error tracking in physics problems.
hana.e.kim
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Homework Statement



A 45.0 cm diameter wheel accelerates uniformly from 205 rpm to 385 rpm in 7.5 s. How far will a point on the edge of the wheel have traveled in this time?

Homework Equations



w=omega
v=initial omega
a=angular acceleration
r=radius
h=theta
t=time
s=distance traveled.

w^2=v^2 + 2ah
a=(w-v)/t
h=s/r

The Attempt at a Solution



So, I converted 205 rpm and 385 rpm to rad/s. Then I found angular acceleration by using the formula: a=(w-v)/t. Then I plugged everything into the equation: w^2=v^2 + 2ah and solved for h(theta). Then I converted h(theta), which was in radians, to meters by multiplying it by the radius because h(theta)=s/r. Apparently that's the wrong way though, so if anyone could help me out, I'd love him/her forever. Thank you!
 
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Can you show your calculations? It's much easier to track down an error that way.
 
Actually, I figured out how to do it. Thanks anyway!
 
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