1-21. A linear machine has a magnetic flux density of 0.5 T directed into the page, a resi...

1-21. A linear machine has a magnetic flux density of 0.5 T directed into the page, a resistance of 0.25 a bar length l = 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?