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1. Homework Statement
Block A in the figure View Figure weighs w_1 and block B weighs w_2. The coefficient of kinetic friction between all surfaces is u_k.
Find the magnitude of the horizontal force \vec{F} necessary to drag block B to the left at constant speed if A is held at rest (figure (b)).
2. Homework Equations
F = ma
a = 0
3. The Attempt at a Solution
I attempted by drawing two FBDs for A and B. I have for
B: w_2 downward, F_aonb downward, normal force upward, F to the left dragging, and fk_ground
A: w_1 downward, normal force upward, F_bona, and fk_ab
Then I solved for the normal force and I got n = (w_1+w_2)/2 and then I plugged it into the fk = ukn, but well wrong answer.
I have a few questions because I don't really understand the whole picture. There's two frictional forces acting on B right? From A and from the ground? Is this correct? Also, the normal force for both B and A...are they the same or are they different? They're different right?
Block A in the figure View Figure weighs w_1 and block B weighs w_2. The coefficient of kinetic friction between all surfaces is u_k.
Find the magnitude of the horizontal force \vec{F} necessary to drag block B to the left at constant speed if A is held at rest (figure (b)).
2. Homework Equations
F = ma
a = 0
3. The Attempt at a Solution
I attempted by drawing two FBDs for A and B. I have for
B: w_2 downward, F_aonb downward, normal force upward, F to the left dragging, and fk_ground
A: w_1 downward, normal force upward, F_bona, and fk_ab
Then I solved for the normal force and I got n = (w_1+w_2)/2 and then I plugged it into the fk = ukn, but well wrong answer.
I have a few questions because I don't really understand the whole picture. There's two frictional forces acting on B right? From A and from the ground? Is this correct? Also, the normal force for both B and A...are they the same or are they different? They're different right?
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