1.1 Introduction
1.1 Oscillations or Vibrations
1.1 Oscillations or Vibrations some important points
1.1 Wave Quantities
1.1 Wave Properties
1.1 Wave Types
1.1 Speed of Waves
1.1 Simple Harmonic Motion
1.1 Derivation of Period and Frequency for SHM
1.1 Energy in Simple Harmonic Motion
1.1 SHM & Simple Pendulum
1.1 Reflection and Transmission
1.1 Summary
Unit 1.1 Multiple Choice Questions - Waves
Unit 1.1 Multiple Choice Answers - Waves


Unit 1.1 Oscillations or Vibrations

Why do most objects vibrate when given an impulse?

Many objects vibrate or oscillate (at least briefly) because most solids are elastic when given an impulse.

How do physicists describe waves?

Mechanical oscillations or vibrations are fully described on the basis of Newtonian mechanics.

Mechanical oscillations.

— A rocking chair,rocking chair an object on the end of a spring, spring a tuning fork,tuning fork the balance wheel of an old watch, a pendulum, a plastic ruler held firmly over the edge of a table and gently struck, vibrating ruler the strings of a guitar or piano.

spring mass oscillation

energy in spring mass system

— Cars oscillate up and down on bumpy roads.

— Buildings, trees and bridges, etc. vibrate when traffic passes or in a strong wind.

— Atoms oscillate within a moleculeco3.

— Atoms of a solid oscillate about their relatively fixed positions.

Electrical oscillations

— Occur in circuits with coils and capacitors.

lc circuit1

Electromagnetic Oscillations

— Occur in Electromagnetic Waves like Gamma & X Rays, Visible light, UV, infra red & microwaves, radio and TV waves.

electromagnetic wave

Vibrations and wave motion are intimately related.

— Waves have as their source a vibration.

— When a mechanical wave travels through a medium, the medium oscillates.

Some simple mechanical waves can be seen in

— Water like ocean waves

— Vibrating strings.

string wave

Less easily seen are:

— sound waves

— earthquake waves (some of which are sound waves)

earthquake wave


Other kinds of waves are:

— Electric waves (like alternating current)

— Electromagnetic waves (including light).


Exercise 1.1.2

What is a wave?


Concept by Kishore Lal. Programmed by Kishore Lal... Copyright © 2015 Kishore Lal. All rights reserved.