A PMMC ammeter has a coil of 100 turns with a resistance of 10 0, the effective depth and a width of the coil are of 3 mm and 2.5 cm respectively. The meter has the flux density of 100mWb/m2 , and the spring used has a constant of 2 x 10-6 Then, calculate, a) Deflection angle, when it measures 0.015mA. b) Deflection torque exerted on the pointer, when it measures 0.02mA. c) Analyze the relationship between no of turns of the moving coil and the torque produced in a PMMC instrument.

A PMMC ammeter has a coil of 100 turns with a resistance of 10 0, the effective depth and a width of the coil are of 3 mm and 2.5 cm respectively. The meter has the flux density of 100mWb/m2 , and the spring used has a constant of 2 x 10-6 Then, calculate, a) Deflection angle, when it measures 0.015mA. b) Deflection torque exerted on the pointer, when it measures 0.02mA. c) Analyze the relationship between no of turns of the moving coil and the torque produced in a PMMC instrument.

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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