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A screen is placed 90 cm away from an object. The image of the object on the screen is formed by a convex lens at two different locations separated by 20 cm. Find the focal length of lens.
08
Nov
A screen is placed 90 cm away from an object. The image of the object on the screen is formed by a convex lens at two different locations separated by 20 cm. Find the focal length of lens. A screen is placed 90 cm away from an object. The image of the object on the [...]
A concave lens forms the image of an object such that the distance between the object and image is 10 cm and the magnification produced is 1/4. The focal length of the lens will be
08
Nov
A concave lens forms the image of an object such that the distance between the object and image is 10 cm and the magnification produced is 1/4. The focal length of the lens will be A concave lens forms the image of an object such that the distance between the object and image is 10 [...]
The distance between an object and a divergent lens is m times the focal length of the lens. The linear magnification produced by the lens is
08
Nov
The distance between an object and a divergent lens is m times the focal length of the lens. The linear magnification produced by the lens is The distance between an object and a divergent lens is m times the focal length of the lens. The linear magnification produced by the lens is November 8, 2020 [...]
The image of an electric bulb fixed in a wall is to be obtained on the wall opposite to it at a distance of 3m. The maximum possible focal length of the convex lens is
08
Nov
The image of an electric bulb fixed in a wall is to be obtained on the wall opposite to it at a distance of 3m. The maximum possible focal length of the convex lens is The image of an electric bulb fixed in a wall is to be obtained on the wall opposite to it [...]
A thin glass (refractive index 1.5) lens has optical power of −8 D in air. Its optical power in a liquid medium with refractive index 1.6 will be:
08
Nov
A thin glass (refractive index 1.5) lens has optical power of −8 D in air. Its optical power in a liquid medium with refractive index 1.6 will be: A thin glass (refractive index 1.5) lens has optical power of −8 D in air. Its optical power in a liquid medium with refractive index 1.6 will [...]
The power of a biconvex lens is 10 dioptre and the radius of curvature of each surface is 10 cm. Then the refractive index of the material of the lens is :
08
Nov
The power of a biconvex lens is 10 dioptre and the radius of curvature of each surface is 10 cm. Then the refractive index of the material of the lens is : The power of a biconvex lens is 10 dioptre and the radius of curvature of each surface is 10 cm. Then the refractive [...]
Two thin equiconvex lenses each of focal length 0.2 m are placed coaxially with their optic centres 0.5m apart. Then find the focal length of the combination is
08
Nov
Two thin equiconvex lenses each of focal length 0.2 m are placed coaxially with their optic centres 0.5m apart. Then find the focal length of the combination is Two thin equiconvex lenses each of focal length 0.2 m are placed coaxially with their optic centres 0.5m apart. Then find the focal length of the combination [...]
The size of the image of an object, which is at infinity, as formed by a convex lens of focal length 30 cm is 2 cm. If a concave lens of focal length 20 cm is placed between the convex lens and the image at a distance of 26 cm from the convex lens, calculate the new size of the image
08
Nov
The size of the image of an object, which is at infinity, as formed by a convex lens of focal length 30 cm is 2 cm. If a concave lens of focal length 20 cm is placed between the convex lens and the image at a distance of 26 cm from the convex lens, calculate [...]
The power of convex lens is 2 dioptres. its power is to be reduced to 1.5 dioptres, by pitting another lens in combination with it. Which of the following lenses will serve the purpose ?
08
Nov
The power of convex lens is 2 dioptres. its power is to be reduced to 1.5 dioptres, by pitting another lens in combination with it. Which of the following lenses will serve the purpose ? by pitting another lens in combination with it. Which of the following lenses will serve the purpose ? The power [...]
A,B and C are the parallel sided transparent media of refractive index n1,n2 and n3 respectively. They are arranged as shown in the figure. A ray is incident at an angle θ on the surface of separation of A and B which is as shown in the figure. After the refraction into the medium B, the ray grazes the surface of separation of the media B and C. Then, Sinθ =
08
Nov
A,B and C are the parallel sided transparent media of refractive index n1,n2 and n3 respectively. They are arranged as shown in the figure. A ray is incident at an angle θ on the surface of separation of A and B which is as shown in the figure. After the refraction into the medium B, [...]