An electric motor rotating a workshop grinding wheel at a rate of 114 rev/min is switched off. Assume the wheel has a constant negative angular acceleration of magnitude 2.10 rad/s2.

Question

(a) How long does it take for the grinding wheel to stop?

Answer 1

wf=0=wi+2at
0=114*2PI/60 + 2(-2.10)t
solve for time, t

Answer 2

6.09