NCERT Solutions for Class 12 Physics Chapter 10: Wave Optics

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NCERT Solutions for Class 12 Physics Chapter 10 Wave Optics are given in this article. The section of optics dealing with the behaviour of light and its wave characteristics is called wave optics. According to the wave theory of light, light is a form of energy that travels through a medium in the form of a transverse wave.

Class 12 Physics Chapter 10 along with Ray Optics belong to Unit 6 Optics which has a weightage of 18 marks with Unit 5 Electromagnetic Waves in the CBSE Class 12 Physics Exam. NCERT Solutions for Class 12 Physics Chapter 10 deals with multiple phenomena like the Huygens Principle, polarisation, coherent light, diffraction, and brewster’s law where the ray approximation of geometrical optics can not happen, and more.

Download PDF: NCERT Solutions for Class 12 Physics Chapter 10

NCERT Solutions for Class 12 Physics Chapter 10

The NCERT solutions for class 12 physics chapter 10: Wave Optics are given below –

Class 12 Physics Chapter 10 – Topics Covered

The locus of all the particles that are vibrating in the same phase at any instant is known as wave front.

A wavefront is therefore a surface with the same phase of vibrating particles at any instant of time at every point on it.

Huygens’ Principle states –
(i) Every point on a wavefront behaves like a source of light and emits secondary wavelets.
(ii) The secondary wavelets spread in all directions in a vacuum with a speed equal to the velocity of light.
(iii) The envelope of a wavefront of secondary wavelets, along the forward direction gives the new position of a wavefront.

Huygens’ principle determines the shape of the wave front at any point in time. It allows to determine the shape of the wavefront at a later point of time.

When a source of light is a point source, the wavefront is spherical

Amplitude (A) is inversely proportional to the distance x i.e.,

A ∝ 1/x

∴ Intensity (I) ∝ (Amplitude)²

When a source of light is linear, the wavefront is cylindrical.

Amplitude (A) ∝ 1/√x

∴ Intensity ∝ (Amplitude)² ∝ 1 / x

Maxwell’s Electromagnetic Wave Theory: Light waves are electromagnetic, therefore, they do not require a material medium for their propagation. Due to its transverse nature, the wave of light undergo polarisation.

The velocity of an electromagnetic wave in a vacuum is:

c = 1/√μo.εo

The velocity of electromagnetic waves in a medium is less than the velocity of light, v < c

v = 1/√μo.εo.εr.μr = c/√μo εr

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Also Read:

Chapter 10 Related Articles
Polarisation of Light	Single Slit Diffraction	Diffraction
Difference between Diffraction and Interference	Destructive Interference	Interference of Waves
Young’s Experiment	Coherent and Incoherent addition of waves	Coherent Sources
Brewster’s law	Braggs Law	Relation between phase difference and path difference

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A beam of red light and a beam of blue light have equal intensities. Which of the following statements is true?
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