What Is Sonic BoomWhen a body moves with a speed which is greater than the speed of sound in air, it is said to be travelling at supersonic speed jet fighters, bullets, etc, often travel at supersonic speed, and when they do so, they produce a sharp, lo…

What is Sound and How is it ProducedSound is a form of energy that produces the sensation of hearing in our ears. Frequency range of audible sound for human is between 20Hz to 20 KHzSound need Material to Travel: You have learnt in previous section that…

Equations Of Motion For Freely Falling Object Since the freely falling bodies fall with uniformly accelerated motion, the three equations of motion derived earlier for bodies under uniform acceleration can be applied to the motion of freely falling bodi…

Human Ear Structure And FunctionWe have just learnt how sound vibrations from a source propagate through the air and reach our ears. Let us now discuss how our ears actually ‘hear’ these sound vibrations. The ear can be broadly classified into three par…

What Is UltrasoundThe sound waves having frequency higher than 20,000 Hz is called ultrasonic waves or ultrasound. Human beings cannot hear ultrasound. Dogs, bats and dolphins can hear ultrasound. For example bats and dolphins can hear sound waves havin…

Characteristics of Sound WavesSound travels in the form of a wave. Waves are characterized by three basic quantities. They are frequency, speed, and amplitude. Two of the main characteristics of sound are pitch and loudness, which in turn are determined …

Relation Between Wave Velocity, Frequency And Wavelength For A Periodic Wave\( \text{wave velocity}=\frac{\text{distance covered}}{\text{Time}\,\,\text{taken}} \) \( =\frac{\text{wave}\,\text{length}}{\text{Time}\,\text{taken}} \) \( \text{or v}=\frac{\l…

How A Rainbow Is FormedA rainbow is a natural spectrum appearing in the sky after a rain shower. It is caused by dispersion of sunlight by tiny water droplets, present in the atmosphere. A rainbow is always formed in a direction opposite to that of the S…

What Are The Defects Of VisionThe major defects of vision are:Short sightedness or myopia.Long sightedness or hypermetropia.PresbyopicAstigmatism1. Short sightedness or myopiaSymptoms: Eye cannot see clearly beyond a certain distance. It means that the f…

Dispersion Of White Light By A Glass PrismWhat happens when light falls on the surface of a compact disc (CD) or a prism? We see that when light falls on a CD or. a prism, it splits up into its many colours. The process of splitting up of white light int…