Physics
Why does the focal length of a lens increase when it is put in water?
Wiki User
June 20, 2009 9:03AM
Light changes direction when it goes from one medium to another for two reasons. One is because it is a wave and other is because the light travels different speeds in the two mediums.
Light travels the speed c in vacuum and it travels the slower speed 3/4c in water and even the slower speed 2/3c in glass.
When the lens is in air the difference in speed is 2/3c versus c. When it is in water the difference in speed is 2/3c versus 3/4c. The difference in speed is smaller when it is in water and so the light bends less. The light bending less corresponds to a longer focal length.
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How do you find the new focal length when the lence is put in to the water?
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What will happen to the focal length of a lens if it is cut into half vertically?
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Does the focal lens length have three classifications?
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If a telescope has an objective lens of 3 inches what is the focal length?
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What is the focal length of a convex lens?
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What is defined as the distance between a lens and its focal point?
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Explain how the focal length of a convex lens changes as the sides of the lens become less curved?
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Which lens in a refracting telescope has a shorter focal length?
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How does change in the thickness of lens change the focal length of lens?
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Does the focal length of a spherical mirror or lens change when placed under water?
i do not think so because a mirror an a lens is two same things
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or bend the water so that can change the focal length between the
mirror and the lens
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What is the focal length formulae?
For a lens ...
1/image distance + 1/object distance = 1/focal length of the
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How does thickness of convex lens affect focal length?
The thicker the lens is, the shorter the focal length will be,
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Will the focal length of a lens change when put in water?
A careful reading of the question raises the uncomfortable
suspicion that it might be
very difficult to put the focal length in water.
However, it's quite possible to put the lens itself in water.
When that's done, it's quite
likely that the lens's focal length has changed. The refractive
indexes of both materials ...
the substance of which the lens is made and the medium around it
... are both involved in
determining its focal length.
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Difference between focal point and focal length?
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the focal point to the lens. Same for a convex lens, except that
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How can you calculate the focal length of a lens?
Basically, the focal length is the distance from the center
of the lens to the focal point or the principal foci.
The calculations will depend on the curvature of the lens, the lens
thickness, and the refractive index of the material that the lens
was made out of. Wikipedia has a great description of lens focal
length, see the link to this article in the related link section
below.
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Why does the focal length of a mirror not depend on the mirror material when the focal length of a lens does depend on the lens material?
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Will focal length of a convex lens change when immersed in water?
yes. By lens formula the relative refractive index will change.
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Will the focal lengths of concave and convex lens change in water?
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