Principle of Superposition The principle of superposition states that where two or more waves meet, the total displacement at any point is the vector sum of the displacements that each individual wave would cause at that point. Coherent Wave Two wave sources which are coherent have same frequency or have constant phase difference. Interference The … Read more

Diffraction of Sound Wave

Diffraction of Sound Wave Experiment Observation The street cleaner can hear the sound of the radio even though it is behind an obstacle. Explanation The sound of the radio spreads around the corner of the wall due to diffraction of sound wave.

Diffraction of Light Wave

Diffraction of LightWave Pin Hole Experiment Light is diffracted when passes through a pinhole. The diffraction pattern is made up of alternating bright and dark ring. Single Slit Experiment Light is diffracted if it passes through a narrow slit. The diffraction pattern is made up of the bright bands and dark bands of different width. … Read more


Diffraction Diffraction is the spreading of a wave when it travels through an opening or a small obstacle. (Diffraction happen when waves pass through an opening) (Diffraction happen when waves encounter an obstacle) Characteristics of Diffracted Wave Wavelength does not change. Frequency does not change. Speed of diffracted does not change. The amplitude of the … Read more

Refraction of Sound Wave

Refraction of Sound Waves Experiment 1 Result The amplitude of the sound wave increases when a balloon filled with Carbon dioxide is placed between the speaker and the microphone. Explanation Carbon dioxide is denser than air. The sound wave is refracted approaching the normal when the wave propagates from the air into the balloon, and … Read more

Refraction of Light Wave

Refraction of Light When light travels one medium to another of differing density, its speed changes. Speed of light is higher in a medium of less density as compare with one higher density. The change in velocity of light when it travels from one media to another of different density results in the refraction phenomenon. … Read more

Refraction in Daily Life

Refraction in Daily Life The effect of refraction causes seaside near to a cape is stony while sea near to a bay is sandy. At the middle of the sea, the wavefront is a linear line. This linear form is due to the nearly equal similar depth of water. When waves move close to the … Read more

Refraction of Waves at a Boundary

Refraction of Waves at a Boundary Refraction is the change in direction of propagation when a wave moves from one medium to another medium. It is caused by the change of the speed of the wave when moving from one medium to another. For water waves, refraction occurs when the waves move from one region … Read more

Speed of Waves

Speed of Water Waves When straight waves pass from deep to shallow water, their wave-length becomes shorter speed decreases frequency remain unchanged This can be illustrated by placing a piece of rectangular Perspex of suitable thickness in the tank to reduce the local water depth. The figure below shows the wavefront diagram of the wave … Read more