A turntable rotates counterclockwise at 78 rpm. A speck of dust on the turntable is at 0.44 rad at t=0 ,What is the angle of the speck at t = 7.9 s? Your answer should be between 0 and 2π rad.
Convert rpm in radians
ω = 78rpm
= 78*2π/60s
= 8.164 rad/s
angular displacement when t = 7.9s
θ = 8.164 rad/s * 7.9 = 64.49 rad
64.49 + .44= 64.93
64.93/2π
=10.33 revolutions
remove the full number of revolutions.
=.33
=.33 x 2π
=2.07 or 2.1 radians
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