This textbook offers a through understanding about the concepts of Biomechanics, Physics and their applications in Physiotherapy. The concepts have been explained with suitable examples and necessary problems for easy understanding

Biomechanics, Electronics and Electrotherapy, First Edition

Dr. M. Seetha, Mrs. V. Mahalakshmi

Published by Yes Dee Publishing Pvt Ltd

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© 2024 by Yes Dee Publishing

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ISBN: 978-93-88005-51-7

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Dedication

to
all our family members
for providing moral support in completing this book

Contents

Foreword

Preface

Acknowledgements

Chapter 1 Mechanics

1.1 Mechanics and Biomechanics

1.1.1 Physical Quantities

1.1.2 Speed, Velocity and Acceleration

1.1.3 Work, Energy and Power

1.1.4 Momentum

1.2 Force

1.2.1 Diagrammatic Representation of Forces

1.2.2 Classification of Forces

1.2.3 Composition and Resolution of Forces

1.2.4 Angle of Pull

1.3 Newton’s Laws

1.3.1 Newton’s First Law

1.3.2 Newton’s Second Law

1.3.3 Newton’s Third Law

1.4 Friction

1.4.1 Friction on the Body

1.4.2 Friction in Devices

1.4.3 Reduction of Friction

1.5 Levers

1.5.1 Classification of Levers

1.5.2 Application of Levers in Physiotherapy

Chapter 2 Gravity and Elasticity

2.1 Gravity

2.1.1 Line of Gravity

2.1.2 Centre of Gravity

2.2 Position of Gravity in Human Body

2.2.1 Equillibrium

2.2.2 Centre of Gravity

2.2.3 Line of Gravity

2.2.4 Base of Support

2.2.5 Stability

2.2.6 Types of Equilibrium

2.3 Elasticity

2.3.1 Load

2.3.2 Stress

2.3.3 Strain

2.3.4 Hooke’s Law

2.3.5 Stress-Strain Curve

2.4 Springs

2.4.1 Springs in Parallel

2.4.2 Springs in Series

2.4.3 Properties of Spring

2.4.4 Application

2.5 Pulleys

2.5.1 Fixed Pulleys

2.5.2 Movable Pulleys

Chapter 3 Current Electricity

3.1 Fundamentals of Electric Current

3.1.1 Bound and Free Electrons

3.1.2 Electron Flow

3.1.3 Dynamic and Static Electric Charges

3.1.4 Potential and Capacitance

3.1.5 Difference of Potential and Electromotive Force

3.2 DC and AC Currents

3.2.1 Frequency, Wavelength and Amplitude

3.2.2 Phase of a Sine Wave

3.2.3 Average and RMS Value of a Sine Wave

3.3 Conductors and Insulators

3.4 Ohm’s Law

3.5 Resistance

3.5.1 Resistances in Series Connection

3.5.2 Resistances in Parallel Connection

3.6 Low, Medium and High Frequency Currents

3.6.1 Low Frequency Currents

3.6.2 Medium Frequency Currents

3.7 Effects of Electric Current

3.7.1 Thermal Effect of Electric Current

3.7.2 Chemical Effect of Electric Current

3.7.3 Magnetic Effect of Electric Current

3.8 Electric and Earth Shock

3.8.1 Electric Shock

3.8.2 Earth shock

Chapter 4 Capacitors and Rheostat

4.1 The Capacitor

4.2 Capacitance of a Capacitor

4.3 Types of Capacitor

4.4 Electric Field of a Capacitor

4.5 Charging and Discharging a Capacitor

4.6 Application of Capacitor in the Physiotherapy Department

4.7 The Rheostat

4.7.1 Construction of the Rheostat

4.7.2 Variable Resistance or Series Rheostat

4.7.3 Potentiometer or Shunt Rheostat

4.8 Application of Rheostat in the Physiotherapy Department

Chapter 5 Electronics