question_answer

Two blocks of masses \[{{m}_{1}}\] and \[{{m}_{2}}\] are placed in contact with each other on a horizontal platform. The coefficient of friction between the platform and the two blocks is the same. The platform moves with an acceleration. The force of interaction between the blocks is  

A) zero, only if \[{{m}_{1}}={{m}_{2}}\]

B) non-zero, when \[{{m}_{1}}>{{m}_{2}}\]

C) non-zero, when \[{{m}_{1}}<{{m}_{2}}\]

D) zero in all cases