Kinetics - Body Translating in a Plane
Example: (continued) The FBD's of each part are shown below.
First check equilibrium. F = T, 2T = P, P = WB = 4 WA
So F = (1/2)P = 2 WA and F = μ N = μ WA For equilibrium μ must equal 2.
But μ is only 1/4. So starting from rest, block A will accelerate to the right.
Next relate the accelerations of block A and block B using kinematics.
See the figure below.
The length, L, of the cord is: x + (π/4)r + y + π(2r) + y + k = L giving ˗ dx/dt + 2 dy/dt = 0
Or for accelerations d2x/dt2 = 2 d2y/dt2. i.e. aA = 2 aB
Click here to continue with this example.
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