An electric fan has blades of length 25 cm measured from the axis of rotation. If the fan is rotatin

Question

An electric fan has blades of length 25 cm measured from the axis of rotation. If the fan is rotating at 120 rpm , the acceleration of a point on the tip of the blade is

Professor PC Thomas Classes · Answer

(a) : Frequency of rotation $
u=120 \mathrm{~rpm}=2 \mathrm{~rps}$ \ length of blade $r=25 \mathrm{~cm}=0.25 \mathrm{~m}$ \ Centripetal acceleration $a=\omega^{2} r=(2 \pi 
u)^{2} r$ \ $=4 \pi^{2} 
u^{2} r=4 \pi^{2}(2)^{2}(0.25)=4 \pi^{2} \mathrm{~m} \mathrm{~s}^{-2}$