 An oscillating or vibrating motion in which a point or body moves back and forth along a line about a fixed central point produces waves.  An oscillating or vibrating system acts as the source of waves which transfer energy from one point to another (without transferring mass).

Examples of waves: (a)Light waves are produced as a result of vibrations of electrons in an atom. (b)Sound waves are produced by vibrating mechanical bodies such as guitar strings or tuning fork. (c)Water waves are produced by a disturbance (or vibration) on a still water surface.

 A wavefront is a line or plane on which the vibrations of every points on it are in phase and are at the same distance from the source of the wave.

WAVE FRONT

 When a wave travels through a medium,the particles of the medium vibrate about their equilibrium positions.  However, the particles of the medium do not travel in the direction of the wave.  A wave transfer energy and the momentum from the source of the wave ( the oscillating or vibrating system) to the surrounding.

oA transverse wave is a wave in which the vibration of particles in the medium is at right angle ( perpendicular) to the direction of propagation of the wave. oExample of transverse waves are water waves and light waves.

Transverse Waves A transverse wave is a wave in which particles of the medium move in a direction perpendicular to the direction which the wave moves.

 A longitudinal wave is a wave in which the vibration of particles in the medium is along (parallel to) the direction of propagation of the wave. Direction of waves propagation and direction of vibration

 The amplitude, A, of a vibrating system is the maximum displacement from its equilibrium position. It is measure of height of the wave crest or depth of the wave trough.  The period, T, or a vibrating system is the time taken to complete an ascillation.  A complete oscillation may be referred as the movement of a vibrating system from one extreme position to the other and back to the same position.

Oscillating System Oscillating system consists of: –Amplitude –Period –Frequency –Wavelength –Wave speed MAIN MENU

Displacement – Time Graph Peak Period s/cm t/s Amplitude, a MAIN MENU

Displacement – Distance Graph Peak Wavelength s/cm x/cm Amplitude, a MAIN MENU

Frequency, f  Numbers of oscillation in one second.  Unit : Hertz (Hz)  f = 1 T MAIN MENU A B C

Wave Speed, v Wave speed, v depends on wavelength, and frequency, f. Wave speed, v = f »Velocity = wavelength x frequency MAIN MENU

1)If the vibration of a wave are at right angles to the direction of the wave, it is called a _____________ wave. An example of this type of wave is ____________. 2)If the vibration of a wave are along the direction of the wave, it is called a ___________ wave. An example of this type of wave is _______________. 3)Given a string tied to a pole, how would you shake the string in order to produce (a) a transverse wave? (b) A longitudinal wave? 4) A wave carries energy from ____________ to _______________, without any transferring of the _________________.

5)The wavelength of a wave is the ______________ between two successive ______________ or ______________. 6)The frequency is the number of ________________ oscillations made in _____________ second. The unit for frequency is _______________. 7)The velocity of wave is equal to ______________ multiplied by _______________. 8)The time taken for a vibrating system to make a complete oscillation is known as ______________. 9)The number of complete oscillation made by a vibrating system is known as ___________________. 10)The distance traveled by a wave in one second is known as ______________.

Mr. MazzReeMie ZaiNAL AbiDiN