33.1 Introduction 33.2 Development and Measurement of Torque 33.3 Prony Brake 33.4 Two-Scale Prony Brake 33.5 Dynamometer 33.6 Back Electromotive Force in a Motor 33.7 Classification of Motors 33.8 Construction 33.9 Characteristics of d.c. Motors 33.10 Relation between Torque and Speed of a Motor 33.11 Direct-Current, Motor Starting Problems 33.12 D.c. Starting Switch 33.13 D.c. Motor Reversing Summary Multiple Choice Questions (MCQ) Conventional Questions (CQ)