NCERT Solutions for Class 11 Physics, Chapter 15 - Waves

Waves have been considered to be fascinating to humans since times immemorial. They are known as a disturbance which travels through a material medium because of a repeated periodic motion of the particles without any physical transportation of the matter. The dual nature of light is well documented, with light exhibiting particle nature as well as wave nature. The CBSE prescribed NCERT Physics for Class 11 Chapter 15- Waves consists of the following sections and sub-sections.

Let us take a look at the subtopics of Class 11 Physics, Chapter 15, Waves.

15.1. Introduction

15.2. Transverse And Longitudinal Waves

15.3. Displacement Relation In A Progressive Wave.

15.3.1. Amplitude And Phase.

15.3.2. Wavelength And Angular Wave Number.

15.3.3. Period, Angular Frequency And Frequency.

15.4. The Speed Of A Travelling Wave

15.4.1. Speed Of A Transverse Wave On A Stretched String.

15.4.2.  Speed Of A Longitudinal Wave(Speed Of Sound)

15.5. The Principle Of Superposition Of Waves

15.6. Reflection Of Waves

15.6.1. Standing Waves And Normal Waves

15.7. Beats

15.8. Doppler Effect.

15.8.1. Source Moving: Observer Stationery

15.8.2. Observer Moving: Source Stationery

15.8.2. Both Source And Observer Stationery

In class 11 Physics, Chapter 15, you will learn:

Section 15.1: In this section, you will learn with the definition of Waves according to Physics. They transfer energy from one point to another by means of propagation.

Section 15.2: In this section, you will learn about Moving Transverse waves have their oscillations perpendicular to the directions of the wave. On the other hand, in the case of Longitudinal Waves, the medium vibrates and propagates in the direction of the wave. More details are explained in Waves Class 11 NCERT.

Section 15.3: In this section, you will learn about derivations, equations, and formulae regarding the terms associated with the study of waves. We shall also be learning in detail about Amplitude, Phase, Angular Number, Wavelength, etc.

Section 15.4: In this section, you will learn that speed is generally counted by initially considering the Speed at the crest part of the wave. We shall also be studying the process to find out the Speed of a Transverse Wave on a Stretched Spring, and Speed of a Longitudinal Wave (which is considered the way to calculate the Speed of sound).

Section 15.5: In this section, you will learn when two or more waves travel through the same medium and at the same time, the total displacement of the medium is equivalent to the sum total of the displacement of the individual waves. This is known as the Superposition of Waves as the waves pass through each other without affecting the other. Go through the textbook for more information.

Section 15.6: In this section, you will learn that waves change direction when the medium of propagation changes. The change occurs at the interface between the two mediums. This is known as Reflection. Reflection is a useful property of waves, and there are many practical applications of it. The topic also distinguishes between Standing and Normal Waves.

Section 15.7: In this section, you will learn that beats occur when two similar frequencies with nearly similar amplitudes are superposed. This principle is used by musicians for tuning their instruments by listening to them. In the case of the sound wave, the frequencies heard are i) the average of the two frequencies ii) a frequency equal to the difference of the two frequencies.

Section 15.8: In this section, you will learn about the Doppler Effect, that refers to the change in the wave’s frequency when the position of the observer changes with respect to the wave source. This phenomenon has various applications- the most notable use being in the field of medical pathology tests.

Find detailed and accurate NCERT Solutions for Class 11 Physics Chapter 15, only at UrbanPro. The answers are also available for download in PDF version under the name NCERT Solutions for Class 11 Physics Waves Pdf.