when a block is placed upon another on a surface wid some friction..surface is horizontal..in wich direction both the blocks will aceelerate....??

wat actually mean by ur question wid out any force applied how actually a body moves..... nd it can be said dat both the blocks move in same dir. bcoz when lower body moves friction b/n bolcks acts backwards nd so according to newtons 3rd law equal nd opp. force will act on the upper block in forward dir. so automatically both the blocks move forward nd other thing is dat if friction b/n blocks is sufficient enough both the blocks move attachedly.if the friction b/n the blocks is not sufficient enough upper block will slip off.

Approved