Given a parallelogram OABC, suppose that OA = a, OC = c and D is the point that divides the side BC equally. Moreover, suppose the line AC meets at the point M. find OM, in terms of the vectors a, b and a scalar r, if OM : MD = r : 1

The higher the astm grain-size number, the coarser the grain is. a)-true b)-false

Ajournal bearing has a journal diameter of 3.250 in with a unilateral tolerance of 20.003 in. the bushing bore has a diameter of 3.256 in and a unilateral tolerance of 0.004 in. the bushing is 2.8 in long and supports a 700-lbf load. the journal speed is 900 rev/min. find the minimum oil film thickness and the maximum film pressure for both sae 20 and sae 20w-30 lubricants, for the tightest assembly if the operating film temperature is 160°f. a computer code is appropriate for solving this problem.

Which of the following ziegler nichols tuning methods the response of the controller to a step input should exhibit an s-shaped curve? a)-open loop mode b)-closed loop mode c)-both modes (open & closed) d)-none of the modes (open & closed)