Please solve q 12?

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1 Answer
Dec 31, 2017

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Let at certain instant the revolving particle be at position A and after half revolution of the circular path it reaches diametrically opposite point at B.If the oppositely directed velocities of the particle at these two poitions be represented by V_A andV_B respectively then let V_A=-5m/s
and V_B=+5m/s

So change in velocity DeltaV=+5-(-5)=10 m/s

The path length from A to B = half of the perimeter =pi*5m.

The time required to traverse this path with speed 5m/s will be Deltat=(pi*5)/5=pi s.

Hence average acceleration

a=(DeltaV)/(Deltat)=10/pi ms^-2