A linear machine has a magnetic flux density of 0.5 T directed into the page, a resistance of 0.25 N, a bar length l = 0.5 m, and a battery voltage of 120 V. a) What is the steady-state speed of the bar if it has a load of 20 N attached to it opposite to the direction of motion? b) What happens to the bar if the flux density falls to 0.45 T? What is its final steady-state speed? c) Suppose Vg is now decreased to 100 V with everything else remaining as in part b). What is the new steady-state speed of the bar? d) From the results for parts b) and c), what are two methods of controlling the speed of a linear machine (or real DC motor)?

A linear machine has a magnetic flux density of 0.5 T directed into the page, a resistance of 0.25 N, a bar length l = 0.5 m, and a battery voltage of 120 V. a) What is the steady-state speed of the bar if it has a load of 20 N attached to it opposite to the direction of motion? b) What happens to the bar if the flux density falls to 0.45 T? What is its final steady-state speed? c) Suppose Vg is now decreased to 100 V with everything else remaining as in part b). What is the new steady-state speed of the bar? d) From the results for parts b) and c), what are two methods of controlling the speed of a linear machine (or real DC motor)?

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter29: Dc Generators

Section: Chapter Questions

Problem 1PA: You are working as an electrician in a large steel manufacturing plant, and you are in the process...

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