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प्रश्न
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?
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उत्तर
Orientation of wavefront is perpendicular to ray. The ray diagram of the situation is shown in figure.
Parallel rays incident on lens L1 forms the image I2 at the focal point of the lens. This image acts as object for the lens L2 Now, due to the converging lens L2 , let final image formed is I which is point image. Hence the wavefront for this image will be of spherical symmetry.
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संबंधित प्रश्न
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- The pattern of wavefront of the light from a distant star intercepted by earth?
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.
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