# two blocks of masses m1 and m2are placed in contact with each other on a horizontal platform . the coefficent of friction between m1 and the platform is 2µ and between block m2 and platform is µ . the platform moves with an acceleration a . the normal reaction between the blocks is:a. zero in all caseb. zero only if m1 = m2c. non zero only if a > 2µgd. non zero if a > µg

148 Points
14 years ago

dear rohan bhatia

in this question relative position of blocks and direction of acceleration of plateform is not given

so i will take a perti cular case

in the diagram normar reaction between block is taken zero

and shown frictional force is maximum

max acc for block m1=2µg

max acc for block m2=µg

clearly when a>µg slipping occure and there must have normal reaction betwwen blocks

so option c and d is correct

normal reaction is zero for a<ug

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