Home
Class 12
PHYSICS
A: The phase difference between any two ...

A: The phase difference between any two points on a wavelength is zero.
R:Corresponding to a beam of parallel rays of light the wavefronts, are planes parallel to one another.

A

IF both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1).

B

If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark(2)

C

IF Assertion is true statement but Reason is false then mark(3)

D

If both Assertion and Reason are false statements, then mark (4)

Text Solution

AI Generated Solution

The correct Answer is:
To solve the assertion and reason question, we will analyze both statements step by step. ### Step 1: Analyze the Assertion **Assertion:** The phase difference between any two points on a wavelength is zero. - **Understanding Phase Difference:** The phase difference (Δφ) between two points in a wave is calculated using the formula: \[ \Delta \phi = \frac{2\pi}{\lambda} \cdot \Delta x \] where Δx is the path difference and λ is the wavelength. - **Path Difference in One Wavelength:** If we consider two points that are one wavelength apart (Δx = λ), the phase difference becomes: \[ \Delta \phi = \frac{2\pi}{\lambda} \cdot \lambda = 2\pi \] This indicates that the two points are in phase, meaning they have completed a full cycle. - **Conclusion for Assertion:** Since the phase difference of 2π corresponds to a complete cycle, the phase difference between any two points on the same wavelength can be considered as zero. Therefore, the assertion is **true**. ### Step 2: Analyze the Reason **Reason:** Corresponding to a beam of parallel rays of light, the wavefronts are planes parallel to one another. - **Understanding Wavefronts:** In wave optics, a wavefront is defined as the surface over which an oscillation is in phase. For parallel rays of light, the wavefronts are indeed planes that are perpendicular to the direction of the rays. - **Conclusion for Reason:** The statement correctly describes the nature of wavefronts for parallel rays of light. Thus, the reason is also **true**. ### Step 3: Relationship Between Assertion and Reason - Although both the assertion and reason are true, the reason does not provide a correct explanation for the assertion. The assertion pertains to phase difference, while the reason discusses the nature of wavefronts. ### Final Conclusion Both the assertion and reason are true, but the reason is not the correct explanation for the assertion. Therefore, the correct option is that both assertion and reason are true, but the reason is not the correct explanation for the assertion.
Promotional Banner

Similar Questions

Explore conceptually related problems

What is the phase difference between any two points lying on the same wavefront

Assertion (A) : The phase difference between any two points on a wave front is zero Reason (R ) : Light from the source reaches every point of the wave front at the same time

In a standing wave the phase difference between two points on either side of a a node will be

The phase difference between the waves arriving at a point from spreading from two corresponding points of successive half period zones is

The phase difference between oscillatory motion of two points separated by a distance of lamda/2 is ( where lamda is the wavelength)

Huygen was the figure scientist who proposed the idea of wave theory of light he said that the light propagates in form of wavelengths. A wavefront is a imaginary surface of every point of which waves are in the same. phase. For example the wavefront for a point source of light is collection of concentric spheres which have centre at the origin w_(1) is a wavefront w_(2) is another wavefront. The radius of the wavefront at time 't' is 'ct' in thic case where 'c' is the speed of light the direction of propagation of light is perpendicular to the surface of the wavelength. the wavefronts are plane wavefronts in case of a parallel beam of light. Huygen also said that every point of the wavefront acts as the source of secondary wavelets. The tangent drawn to all secondary wavelets at a time is the new wavefront at that time. The wavelets are to be considered only in the forward direction (i.e., the direction of propagation of light) and not in the reverse direction if a wavefront w_(1) and draw spheres of radius 'cDeltat' they are called secondary wavelets. Draw a surface w_(2) which is tangential to all these secondary wavelets w_(2) is the wavefront at time t+Deltat Huygen proved the laws of reflection and laws of refraction using concept of wavefront. Q. The wavefrot of a light beam is given by the equation x+2y+3z=c (where c is arbitrary constant) then the angle made by the direction of light with the y-axis is

Huygen was the figure scientist who proposed the idea of wave theory of light he said that the light propagates in form of wavelengths. A wavefront is a imaginary surface of every point of which waves are in the same. phase. For example the wavefront for a point source of light is collection of concentric spheres which have centre at the origin w_(1) is a wavefront w_(2) is another wavefront. The radius of the wavefront at time 't' is 'ct' in thic case where 'c' is the speed of light the direction of propagation of light is perpendicular to the surface of the wavelength. the wavefronts are plane wavefronts in case of a parallel beam of light. Huygen also said that every point of the wavefront acts as the source of secondary wavelets. The tangent drawn to all secondary wavelets at a time is the new wavefront at that time. The wavelets are to be considered only in the forward direction (i.e., the direction of propagation of light) and not in the reverse direction if a wavefront w_(1) and draw spheres of radius 'cDeltat' they are called secondary wavelets. Draw a surface w_(2) which is tangential to all these secondary wavelets w_(2) is the wavefront at time t+Deltat Huygen proved the laws of reflection and laws of refraction using concept of wavefront. Q. Wavefronts incident on an interface between the media are shown in the figure. the refracted wavefront will be as shown in

Huygen was the figure scientist who proposed the idea of wave theory of light he said that the light propagates in form of wavelengths. A wavefront is a imaginary surface of every point of which waves are in the same. phase. For example the wavefront for a point source of light is collection of concentric spheres which have centre at the origin w_(1) is a wavefront w_(2) is another wavefront. The radius of the wavefront at time 't' is 'ct' in thic case where 'c' is the speed of light the direction of propagation of light is perpendicular to the surface of the wavelength. the wavefronts are plane wavefronts in case of a parallel beam of light. Huygen also said that every point of the wavefront acts as the source of secondary wavelets. The tangent drawn to all secondary wavelets at a time is the new wavefront at that time. The wavelets are to be considered only in the forward direction (i.e., the direction of propagation of light) and not in the reverse direction if a wavefront w_(1) and draw spheres of radius 'cDeltat' they are called secondary wavelets. Draw a surface w_(2) which is tangential to all these secondary wavelets w_(2) is the wavefront at time t+Deltat Huygen proved the laws of reflection and laws of refraction using concept of wavefront. Q. Plane are incident on a spherical mirror as shown in the figure. the reflected wavefronts will be

Huygen was the figure scientist who proposed the idea of wave theory of light he said that the light propagates in form of wavelengths. A wavefront is a imaginary surface of every point of which waves are in the same. phase. For example the wavefront for a point source of light is collection of concentric spheres which have centre at the origin w_(1) is a wavefront w_(2) is another wavefront. The radius of the wavefront at time 't' is 'ct' in thic case where 'c' is the speed of light the direction of propagation of light is perpendicular to the surface of the wavelength. the wavefronts are plane wavefronts in case of a parallel beam of light. Huygen also said that every point of the wavefront acts as the source of secondary wavelets. The tangent drawn to all secondary wavelets at a time is the new wavefront at that time. The wavelets are to be considered only in the forward direction (i.e., the direction of propagation of light) and not in the reverse direction if a wavefront w_(1) and draw spheres of radius 'cDeltat' they are called secondary wavelets. Draw a surface w_(2) which is tangential to all these secondary wavelets w_(2) is the wavefront at time t+Deltat Huygen proved the laws of reflection and laws of refraction using concept of wavefront. Q. Certain plane wavefronts are shown in figure the refractive index of medius is

Huygen was the figure scientist who proposed the idea of wave theory of light he said that the light propagates in form of wavelengths. A wavefront is a imaginary surface of every point of which waves are in the same. phase. For example the wavefront for a point source of light is collection of concentric spheres which have centre at the origin w_(1) is a wavefront w_(2) is another wavefront. The radius of the wavefront at time 't' is 'ct' in thic case where 'c' is the speed of light the direction of propagation of light is perpendicular to the surface of the wavelength. the wavefronts are plane wavefronts in case of a parallel beam of light. Huygen also said that every point of the wavefront acts as the source of secondary wavelets. The tangent drawn to all secondary wavelets at a time is the new wavefront at that time. The wavelets are to be considered only in the forward direction (i.e., the direction of propagation of light) and not in the reverse direction if a wavefront w_(1) and draw spheres of radius 'cDeltat' they are called secondary wavelets. Draw a surface w_(2) which is tangential to all these secondary wavelets w_(2) is the wavefront at time t+Deltat Huygen proved the laws of reflection and laws of refraction using concept of wavefront. Q. Certain plane wavefronts are shown in figure the refractive index of medius is