Two crates connected by a rope lie on a horizontal surface (?Fig. E5.37?). Crate A has mass mA, and crate B has mass mB. The coefficient of kinetic friction between each crate and the surface is µk . The crates are pulled to the right at constant velocity by a horizontal force Draw one or more free-body diagrams to calculate the following in terms of mA, mB, and µk: (a) the magnitude of and (b) the tension in the rope connecting the blocks.

Solution 35E Step 1: Free body diagrams Step 2: a) The normal force on the crate A and the gravitational force will cancel each other. And there is no resultant force in the vertical direction. If a force is applied on the crate A, there will be frictional force, fA Wk A Similarly, the normal force on the crate B and the gravitational force will cancel each other. And there is no resultant force in the vertical direction. If a force is applied on the crate B, there will be frictional force, fB Wk B Where, W and W are the weights of crate and crate B A B Resultant of frictional force, f = f + f = AW +B ) k A B But, we know that, W = m g anAW = mAg B B Therefore, f = (m + m )g k A B