00:01
So in this question, they have given that a block of mass m sits on the top of an inclined block, which sits on the top of that rough surface having friction, coefficient, that is mu 2.
00:17
And between these two blocks, we have coefficient friction, that is mu 1.
00:23
And we are applying a horizontal force, that is f, until the force is increased, until the top blocks start to move.
00:36
So we have to calculate the relation between mu 1 and mu 2 so that the bottom block will slide with the top block.
00:47
Right.
00:47
So first of all, we know that on top of block there is a horizontal force.
00:54
So i can say that on top of the block, the frictional force is more than the below block.
01:01
So, let's say on this block, there is a frictional force in this direction, that is fs, and for the lower block, there will be a frictional force in this direction, that is fl.
01:17
So, i can say that the fs should be greater than fl due to this horizontal force.
01:25
Now, what is fs? fs is the frictional force of the upper block...