Problem 3 A linear machine has a magnetic flux density of 0.5 T directed into the page, a resistance of 0.25 02, a bar length = 1.0 m, and a battery voltage of 100 V. (a) What is the initial force on the bar at starting? What is the initial current flow? (b) What is the no-load steady-state speed of the bar? (c) If the bar is loaded with a force of 25 N opposite to the direction of motion, what is the new steady- state speed? What is the efficiency of the machine under these circumstances? VB = 100 V t=0s X. 0.25 92 www B=0.5 T Im

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