<PRE><B>Question 472381</B>
A car traveling at 45 mph. The tires are 30 in in diameter. What is the angular velocity of the tire?
Use feet, not miles.
45 mph = 66 ft/sec
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One rev of the tire is 30*pi inches = 2.5pi feet
66 ft/sec / 2.5pi ft/rev = 26.4/pi rev/sec
1 rev = 2pi radians
26.4/pi * 2pi = 52.8 radians/sec
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52.743 is the right answer, just with roundoff errors
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i got v=rw 
r= 15in(1ft/12in)(1mi/5280ft) so r= 2.37E-4

V= 45mph 

w= v/r 

45mi/2.37E-4(mi)(hr)

which leaves 189873.418/hr(hr/3600sec) 
so w= 52.743/sec 

i dont know how to show work to get rad/sec can i just times it by 1 rad? or was the 45/2.37E-4 the rad?</PRE>