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# DC Pandey Wave Motion Solutions

DC Pandey Waves and Thermodynamics Solutions for Chapter 14 ‘Wave Motion’ will help you in understanding the basics of motion of waves. These concepts are applicable to all kinds of waves such as a wave in a string, sound waves, light, or other electromagnetic waves. In the DC Pandey Physics Chapter, you will learn the difference between transverse and longitudinal waves and the general equation of the wave motion. The other topics include an introduction to plane progressive harmonic wave, speed of a transverse wave on a string, and energy in a wave motion.

DC Pandey Waves and Thermodynamics Wave Motion has a set of 79 questions in 3 exercises will help you in preparing all the topics of DC Pandey Wave Motion in a detailed manner. You will be able to find the amplitude, frequency, and speed of different types of waves after practising these questions. You will also get to study in detail different kinds of wave functions whilst solving the exercise questions. Therefore, solving these questions consistently will prepare you for your CBSE exams as well as the important entrance exams such as the JEE Physics, NEET and BITSAT.

The Instasolv platform will assist you in solving the questions in the DC Pandey Solutions Chapter with a complete conceptual understanding of the topics. The answers by our Physics subject matter experts include appropriate reasoning in each step. We use the simplest possible methods to solve the exercise questions to guide you in developing a strong foundation in waves and thermodynamics. Your consistency summed up with the team-work at the Instasolv platform will yield you good ranks in the exams of your choice.

## Important Topics for DC Pandey Waves and Thermodynamics Solutions Chapter 14: Wave Motion

Introduction to Waves

Wave is a kind of disturbance from the current state of equilibrium that will propagate itself without the movement of matter.

Transverse and Longitudinal Waves

There are 2 types of waves- Transversal and Longitudinal

1. Transversal Waves: In transversal waves, the vibration of the particles of the medium is in the direction which is perpendicular to the direction of the wave.
2. Longitudinal Waves: In the longitudinal waves the vibrations of the [articles of the medium are in the direction which is parallel to the direction of the wave.one that moves parallel to the direction of waves of particles in motion. Such a wave is a straight parallel line above the particle. in the example of a horizontal rope, if one introduces a pulse on the left and the right end, the energy flows from both ends trapping the movements in a parallel motion.

General Equation of Wave Motion

We can assume an element of an elemental mass ‘dm’ and find the forces acting on it in the space ‘dx’. In the case of a small displacement ‘dx’, the horizontal force is approximately zero and the vertical force, Fy will be given as

where T’ and T are tensional forces acting on dm at an angle of θ2 and θ1 respectively and μ is the mass density δm/δx.

Since the tangent is equal to the slope geometrically, dividing over dx, we will get

which is the same as the equation for a one-dimensional wave with velocity

Thus, taking the second derivative, the final wave equation for wave function f and velocity v for time t is

Plane Progressive Harmonic Wave

A plane progressive harmonic wave is formed when the particles in the medium that the wave is traversing, tend to vibrate in simple harmonic motion.

In a plane progressive harmonic wave, the phase difference between displacement and acceleration of the particle is

For SHM phase difference between displacement and velocity is Π/2 because y=a.sinωt and V=a.cosωt.

Speed of a Transverse Wave on a String

Energy in Wave Motion

Where all the symbols are as described above and k=ω/v.

### Exercise Discussion for DC Pandey Waves and Thermodynamics Solutions Chapter 14: Wave Motion

Introductory Exercises:

• In the introductory exercise 14.1, there are 5 questions based on the wave function and velocity of a propagating wave.
• In 14.2, you will get to solve 4 detailed questions in exercise 14.2 about the amplitude, velocity, frequency, and wave functions.
• The 2 questions in exercise 14.3 are based on the velocity of a transverse wave in a string.
• There are 2 questions in exercise 14.4 based on energy density, intensity, and power in the wave motions.

Exercise for JEE Main:

• There are 9 subjective questions in which you will be required to find the amplitude, velocity, wavelengths, frequency, etc. using the wave equations and concepts of a plane progressive harmonic wave.
• Questions 10-16 are based on the speed of a transverse wave in a string or wires of different materials.
• Questions 17-20 are about the energy in the wave motion.
• There are 21 objective multiple-choice questions in this exercise including all the topics mentioned above.