Physics Class 11 Chapter 14 & 15 Oscillations and waves | 页面 2

Introduction
Waves are everywhere : - Ocean - Earth - Matter ( Probability waves , Predict behavior of e - , particles ) - Sound - > What we hear - Sight - > What we see - Electromagnetic waves ( Power to our homes , Radio & TV , Electronics )
Properties of waves : -Energy -Momentum -Velocity -Linearity
Energy :
- " Like moving objects , moving waves carry energy from one place to another " - J . R . Pierce
- Energy is not transmitted by the media that support waves , but by the waves themselves .
- EM waves from sun to earth have power of 1KW / m 2 . - Plants are supported on this energy and we are supported by plants .
Momentum : Moving waves have momentum when a wave is absorbed or reflected by and object , the wave pushes on that object .
Velocity : It takes time for a wave to go from one place to another . Light : 186,000 Miles / Sec , 300,000 KM / Sec Sound : ( Through air ) ~ 1129 feet / Sec
Oscillations : Motions that repeat themselves . Periodic Harmonic motion : Motion that repeats itself at regular intervals . Simple Harmonic Motion : Harmonic Motion that is sinusoidal .