Physics
A wheel mounted on a stationary axle starts at rest and is given the following angular acceleration: 912t where t is the time after the wheel begins to rotate. Find the number of revolutions that the wheel turns before it stops ( and begins to turn in the opposite direction).
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Happinessdelight

dv/dt = 9  12 t and v(0)= 0
v = 9 t  6 t^2 + constant
when t = 0, v = 0 so constant = 0
v is radians/sec
v = 9 t  6 t^2
at v = 0
0 = t(96t)
so v = 0 at t = 0 as we knew
and
v = 0 at t=9/6 = 3/2 = 1.5
so how far did it go?
x is radians
x = (9/2) t^2  (6/3)t^3 + 0
x = (9/2)(9/4)  (6/3)(9/4)(3/2)
= 81/8  54/12
= (243  108)/24
=135/24 radians
check my arithmetic
divide by 2 pi to get revolutionsposted by Damon
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