If the difference in velocities of light in glass and water is 0 . 25 × 10 8 m / s , find the velocity of light in air. (given: μ g = 1 . 5 , μ w = 4 / 3 )

Given, v w - v g = 0 . 25 × 10 8 m / s μ g = 1 . 5 μ w = 4 3 c = ? We know that refractive index is given by, μ = c v ∴ v = c μ From the question, v w - v g = 0 . 25 × 10 8 c μ w - c μ g = 0 . 25 × 10 8 c 1 μ w - 1 μ g = 0 . 25 × 10 8 c 3 4 - 2 3 = 0 . 25 × 10 8 c × 1 12 = 0 . 25 × 10 8 c = 0 . 25 × 10 8 × 12 c = 3 × 10 8 m / s Therefore, the the velocity of light in air is 3 × 10 8 m / s

If the difference in velocities of light in glass and water is 0 . 25 × 10 8 m / s , find the velocity of light in air. (given: μ g = 1 . 5 , μ w = 4 / 3 )

Given, v w - v g = 0 . 25 × 10 8 m / s μ g = 1 . 5 μ w = 4 3 c = ? We know that refractive index is given by, μ = c v ∴ v = c μ From the question, v w - v g = 0 . 25 × 10 8 c μ w - c μ g = 0 . 25 × 10 8 c 1 μ w - 1 μ g = 0 . 25 × 10 8 c 3 4 - 2 3 = 0 . 25 × 10 8 c × 1 12 = 0 . 25 × 10 8 c = 0 . 25 × 10 8 × 12 c = 3 × 10 8 m / s Therefore, the the velocity of light in air is 3 × 10 8 m / s

A small angled prism of 4 ° deviates a ray through 2 . 48 ° . Find the refractive Index of the prism.

It is given that the prism under consideration is a thin prism. Also, The angle of prism, A = 4 ° Angle of deviation, δ = 2 . 48 ° Let n be the refractive index of the prism. We know that for a thin prism, δ = A n - 1 ⇒ n = δ A + 1 ⇒ n = 1 . 62

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If the difference in velocities of light in glass and water is $0.25 \times 10^{8} m / s$ , find the velocity of light in air. (given: $μ_{g} = 1.5, μ_{w} = 4 / 3$ )

Important Questions on Ray Optics and Optical Instruments

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Physics Crash Course (Based on Revised Syllabus-2023)>Chapter 9 - Ray Optics and Optical Instruments>Exercise>Q 42

Find the speed of light in a medium of refractive index

1.33

and speed of light in air is

c = 3 \times 10^{8} m / s

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Physics Crash Course (Based on Revised Syllabus-2023)>Chapter 9 - Ray Optics and Optical Instruments>Exercise>Q 43

To get three images of a single object, we should have two plane mirrors at an angle of

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Physics Crash Course (Based on Revised Syllabus-2023)>Chapter 9 - Ray Optics and Optical Instruments>Exercise>Q 44

A plano-convex lens of refractive index

μ_{1}

and focal length

f_{1}

is kept in contact with another plano-concave lens of refractive index

μ_{2}

and focal length

f_{2} .

If the radius of curvature of their spherical faces is

R

each and

f_{1} = 2 f_{2},

the

μ_{1}

and

μ_{2}

are related as:

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Physics Crash Course (Based on Revised Syllabus-2023)>Chapter 9 - Ray Optics and Optical Instruments>Exercise>Q 45

Formation of real image using a biconvex lens is shown below:

Question Image

If the whole set up is immersed in water without disturbing the object and the screen positions, what will one observe on the screen?

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Physics Crash Course (Based on Revised Syllabus-2023)>Chapter 9 - Ray Optics and Optical Instruments>Exercise>Q 46

Which of the following is not the case with the image formed by a concave lens?

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Physics Crash Course (Based on Revised Syllabus-2023)>Chapter 9 - Ray Optics and Optical Instruments>Exercise>Q 47

In an optics experiments, with the position of the object fixed, a student varies the position of a convex lens and for each position, the screen is adjusted to get a clear image of the object. A graph between the object distance

u

and the image distance

v,

from the lens, is plotted using the same scale for the two axes. A straight line passing through the origin and making an angle of

45 °

with the

x

-axis meets the experimental curve at

P .

The coordinates of

P

will be

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Physics Crash Course (Based on Revised Syllabus-2023)>Chapter 9 - Ray Optics and Optical Instruments>Exercise>Q 48

A focal length of a thin biconvex lens is 20 cm. When an object is moved from a distance of 25cm in front of it to 50cm, the magnification of its image changes from $m_{25} t o m_{50} .$ The ration $\frac{m_{25}}{m_{50}}$ is

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Physics Crash Course (Based on Revised Syllabus-2023)>Chapter 9 - Ray Optics and Optical Instruments>Exercise>Q 49

A converging lens is to project the image of a lamp 4 times the size of the lamp on a wall at a distance of 10 m from the lamp. The focal length of the lens is

If the difference in velocities of light in glass and water is 0.25×108 m/s, find the velocity of light in air. (given:μg=1.5, μw=4/3)

Important Questions on Ray Optics and Optical Instruments

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If the difference in velocities of light in glass and water is $0.25 \times 10^{8} m / s$ , find the velocity of light in air. (given: $μ_{g} = 1.5, μ_{w} = 4 / 3$ )