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=-5#m/s
and #V_B=+5#m/s

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

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

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#