How do you calculate the speed of sound?

Posted by Tutoria.pk on December 11th, 2020

Speed of Sound

All the waves travel at a certain speed and have the characteristics of wavelength and frequency. Speed of sound is the total distance a sound wave traveled per unit of time. The estimated speed of sound in air is about 343 meters per second. Speed is symbolized by "v" in the equations.

Variations in different mediums

Speed of sound commonly refers to the speed of sound waves in the air but it is different from substance to substance. The sound waves travel faster in liquids and solids as compared to gases. This is due to the distance between particles and molecules. The sound waves are composed of compression waves in solids, liquids and gases however solids also have another type of sound wave called a shear wave. 

In both short and long questions, the topic of sound waves is widely seen in 10th class past papers. 

How to calculate the speed of sound?

The speed of sound waves in any medium can be calculated with the help of frequency and wavelength. The mathematical relationship between speed, frequency, and wavelength is given by the following equation.

Speed = Wavelength * Frequency

Using the symbols v, λ, and f, the equation can be written as

v = f * λ

This equation is useful for solving numerically related to the speed, frequency, and wavelength relationship. The speed of a sound wave depends on the characteristics of the medium through which it travels and the only way to change the speed is to change the properties of the medium such as gasses or liquids. 

Speed of sound in air 

The speed of sound in air in 343 meters per second where t is the temperature of the air in degrees Celsius. Using this equation to determine the speed of a sound wave in air at a temperature of 20 degrees Celsius gives the following solution.

v = 331.3 + (0.6 × t)

v = 331.3 + (0.6 × 20 C) 

v = 331 m/s + 12 m/s

v = 343.3 m/s.

You can find the speed of sound by echo methods from the following formula using different amount of distance. 

v = s/t 

v = 340 ms-1 and t = 0.1 s 

How to prepare the speed of sound topics for exams?

This topic contains a definition, equation, and formulas. We prefer to have a look at the federal board solved past papers before the exams for a better understanding of the upcoming paper. Solved past papers help you to prepare the whole topic in one go. You can get an idea of how to cover the topic if comes in a short question or a long question.