Advertisements
Advertisements
प्रश्न
Using Huygen's wave theory of light, show that the angle of incidence is equal to the angle of reflection. Draw a neat and labelled diagram.
उत्तर
Consider a plane wave AB incident at an angle i on a reflecting surface MN. If v represents the speed of the wave in the medium and if T represents the time taken by the wavefront to advance from point B to C, then distance BC = vt.
In order to construct the reflected wavefront, a sphere of radius = vt is drawn from point A, as shown in the figure. Let CE represent the tangent plane drawn from the point C to this surface.
∴ AE = BC = vt
∠ABC = ∠CEA = 90°
Here AC is common.
∴ ΔEAC ≅ ΔBAC
Hence i = r.
APPEARS IN
संबंधित प्रश्न
Using Huygens's construction of secondary wavelets explain how a diffraction pattern is obtained on a screen due to a narrow slit on which a monochromatic beam of light is incident normally.
Explain the construction of plane wavefront using Huygens’ principle.
What is the shape of the wavefront in the following case?
Light emerging out of a convex lens when a point source is placed at its focus.
What is the shape of the wavefront in the following case?
The portion of the wavefront of light from a distant star was intercepted by the Earth.
Using this principle draw a diagram to show how a plane wave front incident at the interface of the two media gets refracted when it propagates from a rarer to a denser medium. Hence verify Snell's law of refraction.
When the width of the slit is made double the original width, how would this affect the size and intensity of the central diffraction band?
Derive the law of reflection using Huygen’s Wave Theory.
According to Huygen's construction, relation between old and new wavefront is ______.
For light diverging from a point source ______.
- the wavefront is spherical.
- the intensity decreases in proportion to the distance squared.
- the wavefront is parabolic.
- the intensity at the wavefront does not depend on the distance.
Consider a point at the focal point of a convergent lens. Another convergent lens of short focal length is placed on the other side. What is the nature of the wavefronts emerging from the final image?
