Assertion : In the system of two blocks of equal masses as shown, the coefficient of friction between the blocks ( ( ₂ )) is less than coefficient of friction ( ( ₁ )) between lower block and ground. For all values of force (F ) applied on upper block lower block remains at rest. Reason : Frictional force on lower block due to upper block is not sufficient to overcome the frictional force on lower block due to ground

Step-by-step solution

Why assertion is true - For two equal-mass blocks, the maximum static friction at the ground is ( 1(2 mg ) ), which exceeds any friction demand transmitted from the top block because ( 2 < 1 ) limits the interface force first. Hence, the lower block can remain at rest for all applied F. Why reason is correct - The friction exerted by the upper block on the lower is bounded by ( 2 mg ), which is smaller than the maximum ground friction ( 1(2 mg ) ); therefore, this interface force can't overcome ground friction, kee