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Convex lens or concave lens is put inside water, Water’s refractive index is in between air’s and glass’s. … Therefore, when the lens is put in water, then the light ray is bent by smaller amount after refraction. Therefore the ray travels for longer distance before it meets the principal axis.

## What happens when a lens is kept in water?

When any lens or glass slab is immersed in a liquid whose refractive index is equal to that of lens, refractive index of lens will be equal to 1 relative to that liquid. The focal length of the lens in this case, will tend to infinity.

## What happened to the focal length of convex lens when immersed in water?

What happens to focal length of a convex lens when it is immersed in water ? ∴fw>fa, i.e., focal length of lens will increase.

## What happens when concave lens is dipped in water?

when concave lens immersed in water the focal length of lens increases because focal length of lens is directly proportional to refractive index of medium and when immersed in water the medium become more dancer so its focal length increases.

## How will the result change if a convex lens of different refractive indices were used?

Answer: if n decreases, f increases. So if you immerse the convex lens in a liquid whose refractive index is greater than refractive index of material of lens then it will change its nature and become concave lens and thus it will start diverging the rays rather than focusing them on a single point.

## Will the focal length of a lens change when it is submerged in water?

Yes. Focal length changes when lens is immersed in water.

## What happens when a convex lens is immersed in a liquid of higher refractive index than the lens itself?

So if you immerse the convex lens in a liquid whose refractive index is greater than refractive index of material of lens then it will change its nature and become concave lens and thus it will start diverging the rays rather than focusing them on a single point.

## How will the image formed by a convex lens be affected if the lower half of the lens is covered with black paper?

Note: Even if half of the convex lens is covered with a black sheet of paper, the lens will produce a complete image of the object. However, the intensity of the image will be less and the image formed will be less bright as compared to the one formed by a complete convex lens.

## When two convex lenses are in contact with each other what happens to the ray after refraction?

Hence the power of combination is increased which means that the converging capacity is increased. And the focal length is decreased (because focal length is inversely proportional to the power of lens). Therefore the ray after refraction will converge at point close to lens than earlier.