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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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Which of the two has a greater power a lens of short focal length or a lens of large focal length?
A lens of short focal length has a greater power (than a lens of large focal length)
What will happen to the focal length of a lens if it is cut into half vertically?
When the lens is cut vertically then the focal length of the lens will increase.the focal length will become approx double.
How does the thickness of a lens affect the focal length of a lens?
More the thickness, less the focal length.
Which lens has a greater power convex lens of focal length 10 cm or a convex lens of focal length 20cm?
Power is inversely related to the focal length. So convex lens of focal length 20 cm has less power compared to that having focal length 10 cm
Will focal length of a convex lens change when immersed in water?
yes. By lens formula the relative refractive index will change. hence the focal lenght increases.
Which of the two has a greater power a lens of short focal length or a lens of large focal length?
A lens of short focal length has a greater power (than a lens of large focal length)
How focal length of a lens change when apparatus immersed in water?
Yes , because when lens is deeped in water its R.I changes & hence focal length is increased
What is the focal length of a lens?
The focal length of a lens refers to the distance from the centre of the lens to the principal foci.
Whats the focal length of a lens?
The focal length of a lens is the distance from the principal foci to the center of the lens.
How do you find the new focal length when the lence is put in to the water?
to find the new focal length when the lens is put into water it becomes the 4 times the focal length in air.
What will happen to the focal length of a lens if it is cut into half vertically?
When the lens is cut vertically then the focal length of the lens will increase.the focal length will become approx double.
Does the focal lens length have three classifications?
yes, focal lens length has three classifications
How does the thickness of a lens affect the focal length of a lens?
More the thickness, less the focal length.
Which lens has a greater power convex lens of focal length 10 cm or a convex lens of focal length 20cm?
Power is inversely related to the focal length. So convex lens of focal length 20 cm has less power compared to that having focal length 10 cm
What is defined as the distance between a lens and its focal point?
focal length of the lens
What is the focal length of a convex lens?
The distance from the centre of the lens to the focal point.
What is the focal length of the convex lens?
The distance from the centre of the lens to the focal point.
