For the simple pendulum shown, I = 200 mm, when θ=30∘,dθdt=−9rads−1, The magnitude of the total acceleration of the pendulum for this position is

Tangential acceleration, for a simple pendulum isaT=gsin⁡θSo, at θ=30∘, we haveaT=gsin⁡30∘=g2=5ms−2Further we know that aC=ℓω2⇒aC=2001000(9)2⇒aC=21081=16.2ms−2Since the total acceleration is     a=aC2+aT2⇒a=(16.2)2+(5)2⇒a=17ms−2