364983
A point source of light is kept below the surface of water \(\left( {{n_w} = \frac{4}{3}} \right)\) at a depth of \(\sqrt 7 m\) . The radius of the circular bright patch of light noticed on the surface of water is ........ \(m\)
1 \(\frac{3}{{\sqrt 7 }}\)
2 3
3 \(\frac{{\sqrt 7 }}{3}\)
4 \(\sqrt 7 \)
Explanation:
Here, Refractive index of water, \({n_w} = \frac{4}{3}\) \(\therefore \;\;\sin C = \frac{1}{{{n_w}}} = \frac{1}{{\left( {\frac{4}{3}} \right)}} = \frac{3}{4}\,\,\,\,[C = critical\,\,angle]\) \( \Rightarrow \tan C = \frac{3}{{\sqrt {{4^2} - {3^2}} }} = \frac{3}{{\sqrt 7 }}\;\;\;\;\;\;(1)\) From figure, \(\tan C = \frac{R}{{\sqrt 7 }}\;\;\;\;\;\;(2)\) Equating (1) and (2) , we get \(\frac{3}{{\sqrt 7 }} = \frac{R}{{\sqrt 7 }} \Rightarrow R = 3\;{\mkern 1mu} m\)
KCET - 2012
PHXII09:RAY OPTICS AND OPTICAL INSTRUMENTS
364984
The refractive index of water is 1.33 . The direction in which a man under water should look to see the setting sun is
364985
The main cause of decrease in intensity of light on refraction is
1 Scattering of light
2 Passing of light from one medium to another
3 Total internal reflection
4 Partial reflection and partial absorption
Explanation:
Conceptual Question
PHXII09:RAY OPTICS AND OPTICAL INSTRUMENTS
364986
The time required for the light to pass through a glass slab (refractive index = 1.5) of thickness \(4\;mm\) is ( \(c = 3 \times {10^8}m{s^{ - 1}}\), speed of light in free space)
1 \({10^{ - 11}}\sec \)
2 \(2 \times {10^{ - 11}}\sec \)
3 \(2 \times {10^{ + 11}}\sec \)
4 \(2 \times {10^{ - 5}}\sec \)
Explanation:
Speed of light in glass slab is \(v = \frac{c}{\mu } = \frac{{3 \times {{10}^8}}}{{1.5}}m{s^{ - 1}}\;\;\;\;\;\;(1)\) The time required for the light to pass through a glass slab of thickness \(4\;mm\) is \(t = \frac{{{\rm{thickness}}}}{{{\rm{velocity}}\left( v \right)}} = \frac{{4 \times {{10}^{ - 3}}m}}{{\frac{{3 \times {{10}^8}m{s^{ - 1}}}}{{1.5}}}}\,\,\,[{\rm{using}}\,(1)]\) \( = 2 \times {10^{ - 11}}{\rm{s}}\)
KCET - 2011
PHXII09:RAY OPTICS AND OPTICAL INSTRUMENTS
364987
Assertion : The colour of the green flower seen through red glass appears to be dark. Reason : Red glass transmits only red light.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
Red glass transmits only red (and absorbs other colors). The green light from green flower is absorbed by red glass and so the flower appears to be black. So correct option is (1).
364983
A point source of light is kept below the surface of water \(\left( {{n_w} = \frac{4}{3}} \right)\) at a depth of \(\sqrt 7 m\) . The radius of the circular bright patch of light noticed on the surface of water is ........ \(m\)
1 \(\frac{3}{{\sqrt 7 }}\)
2 3
3 \(\frac{{\sqrt 7 }}{3}\)
4 \(\sqrt 7 \)
Explanation:
Here, Refractive index of water, \({n_w} = \frac{4}{3}\) \(\therefore \;\;\sin C = \frac{1}{{{n_w}}} = \frac{1}{{\left( {\frac{4}{3}} \right)}} = \frac{3}{4}\,\,\,\,[C = critical\,\,angle]\) \( \Rightarrow \tan C = \frac{3}{{\sqrt {{4^2} - {3^2}} }} = \frac{3}{{\sqrt 7 }}\;\;\;\;\;\;(1)\) From figure, \(\tan C = \frac{R}{{\sqrt 7 }}\;\;\;\;\;\;(2)\) Equating (1) and (2) , we get \(\frac{3}{{\sqrt 7 }} = \frac{R}{{\sqrt 7 }} \Rightarrow R = 3\;{\mkern 1mu} m\)
KCET - 2012
PHXII09:RAY OPTICS AND OPTICAL INSTRUMENTS
364984
The refractive index of water is 1.33 . The direction in which a man under water should look to see the setting sun is
364985
The main cause of decrease in intensity of light on refraction is
1 Scattering of light
2 Passing of light from one medium to another
3 Total internal reflection
4 Partial reflection and partial absorption
Explanation:
Conceptual Question
PHXII09:RAY OPTICS AND OPTICAL INSTRUMENTS
364986
The time required for the light to pass through a glass slab (refractive index = 1.5) of thickness \(4\;mm\) is ( \(c = 3 \times {10^8}m{s^{ - 1}}\), speed of light in free space)
1 \({10^{ - 11}}\sec \)
2 \(2 \times {10^{ - 11}}\sec \)
3 \(2 \times {10^{ + 11}}\sec \)
4 \(2 \times {10^{ - 5}}\sec \)
Explanation:
Speed of light in glass slab is \(v = \frac{c}{\mu } = \frac{{3 \times {{10}^8}}}{{1.5}}m{s^{ - 1}}\;\;\;\;\;\;(1)\) The time required for the light to pass through a glass slab of thickness \(4\;mm\) is \(t = \frac{{{\rm{thickness}}}}{{{\rm{velocity}}\left( v \right)}} = \frac{{4 \times {{10}^{ - 3}}m}}{{\frac{{3 \times {{10}^8}m{s^{ - 1}}}}{{1.5}}}}\,\,\,[{\rm{using}}\,(1)]\) \( = 2 \times {10^{ - 11}}{\rm{s}}\)
KCET - 2011
PHXII09:RAY OPTICS AND OPTICAL INSTRUMENTS
364987
Assertion : The colour of the green flower seen through red glass appears to be dark. Reason : Red glass transmits only red light.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
Red glass transmits only red (and absorbs other colors). The green light from green flower is absorbed by red glass and so the flower appears to be black. So correct option is (1).
364983
A point source of light is kept below the surface of water \(\left( {{n_w} = \frac{4}{3}} \right)\) at a depth of \(\sqrt 7 m\) . The radius of the circular bright patch of light noticed on the surface of water is ........ \(m\)
1 \(\frac{3}{{\sqrt 7 }}\)
2 3
3 \(\frac{{\sqrt 7 }}{3}\)
4 \(\sqrt 7 \)
Explanation:
Here, Refractive index of water, \({n_w} = \frac{4}{3}\) \(\therefore \;\;\sin C = \frac{1}{{{n_w}}} = \frac{1}{{\left( {\frac{4}{3}} \right)}} = \frac{3}{4}\,\,\,\,[C = critical\,\,angle]\) \( \Rightarrow \tan C = \frac{3}{{\sqrt {{4^2} - {3^2}} }} = \frac{3}{{\sqrt 7 }}\;\;\;\;\;\;(1)\) From figure, \(\tan C = \frac{R}{{\sqrt 7 }}\;\;\;\;\;\;(2)\) Equating (1) and (2) , we get \(\frac{3}{{\sqrt 7 }} = \frac{R}{{\sqrt 7 }} \Rightarrow R = 3\;{\mkern 1mu} m\)
KCET - 2012
PHXII09:RAY OPTICS AND OPTICAL INSTRUMENTS
364984
The refractive index of water is 1.33 . The direction in which a man under water should look to see the setting sun is
364985
The main cause of decrease in intensity of light on refraction is
1 Scattering of light
2 Passing of light from one medium to another
3 Total internal reflection
4 Partial reflection and partial absorption
Explanation:
Conceptual Question
PHXII09:RAY OPTICS AND OPTICAL INSTRUMENTS
364986
The time required for the light to pass through a glass slab (refractive index = 1.5) of thickness \(4\;mm\) is ( \(c = 3 \times {10^8}m{s^{ - 1}}\), speed of light in free space)
1 \({10^{ - 11}}\sec \)
2 \(2 \times {10^{ - 11}}\sec \)
3 \(2 \times {10^{ + 11}}\sec \)
4 \(2 \times {10^{ - 5}}\sec \)
Explanation:
Speed of light in glass slab is \(v = \frac{c}{\mu } = \frac{{3 \times {{10}^8}}}{{1.5}}m{s^{ - 1}}\;\;\;\;\;\;(1)\) The time required for the light to pass through a glass slab of thickness \(4\;mm\) is \(t = \frac{{{\rm{thickness}}}}{{{\rm{velocity}}\left( v \right)}} = \frac{{4 \times {{10}^{ - 3}}m}}{{\frac{{3 \times {{10}^8}m{s^{ - 1}}}}{{1.5}}}}\,\,\,[{\rm{using}}\,(1)]\) \( = 2 \times {10^{ - 11}}{\rm{s}}\)
KCET - 2011
PHXII09:RAY OPTICS AND OPTICAL INSTRUMENTS
364987
Assertion : The colour of the green flower seen through red glass appears to be dark. Reason : Red glass transmits only red light.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
Red glass transmits only red (and absorbs other colors). The green light from green flower is absorbed by red glass and so the flower appears to be black. So correct option is (1).
364983
A point source of light is kept below the surface of water \(\left( {{n_w} = \frac{4}{3}} \right)\) at a depth of \(\sqrt 7 m\) . The radius of the circular bright patch of light noticed on the surface of water is ........ \(m\)
1 \(\frac{3}{{\sqrt 7 }}\)
2 3
3 \(\frac{{\sqrt 7 }}{3}\)
4 \(\sqrt 7 \)
Explanation:
Here, Refractive index of water, \({n_w} = \frac{4}{3}\) \(\therefore \;\;\sin C = \frac{1}{{{n_w}}} = \frac{1}{{\left( {\frac{4}{3}} \right)}} = \frac{3}{4}\,\,\,\,[C = critical\,\,angle]\) \( \Rightarrow \tan C = \frac{3}{{\sqrt {{4^2} - {3^2}} }} = \frac{3}{{\sqrt 7 }}\;\;\;\;\;\;(1)\) From figure, \(\tan C = \frac{R}{{\sqrt 7 }}\;\;\;\;\;\;(2)\) Equating (1) and (2) , we get \(\frac{3}{{\sqrt 7 }} = \frac{R}{{\sqrt 7 }} \Rightarrow R = 3\;{\mkern 1mu} m\)
KCET - 2012
PHXII09:RAY OPTICS AND OPTICAL INSTRUMENTS
364984
The refractive index of water is 1.33 . The direction in which a man under water should look to see the setting sun is
364985
The main cause of decrease in intensity of light on refraction is
1 Scattering of light
2 Passing of light from one medium to another
3 Total internal reflection
4 Partial reflection and partial absorption
Explanation:
Conceptual Question
PHXII09:RAY OPTICS AND OPTICAL INSTRUMENTS
364986
The time required for the light to pass through a glass slab (refractive index = 1.5) of thickness \(4\;mm\) is ( \(c = 3 \times {10^8}m{s^{ - 1}}\), speed of light in free space)
1 \({10^{ - 11}}\sec \)
2 \(2 \times {10^{ - 11}}\sec \)
3 \(2 \times {10^{ + 11}}\sec \)
4 \(2 \times {10^{ - 5}}\sec \)
Explanation:
Speed of light in glass slab is \(v = \frac{c}{\mu } = \frac{{3 \times {{10}^8}}}{{1.5}}m{s^{ - 1}}\;\;\;\;\;\;(1)\) The time required for the light to pass through a glass slab of thickness \(4\;mm\) is \(t = \frac{{{\rm{thickness}}}}{{{\rm{velocity}}\left( v \right)}} = \frac{{4 \times {{10}^{ - 3}}m}}{{\frac{{3 \times {{10}^8}m{s^{ - 1}}}}{{1.5}}}}\,\,\,[{\rm{using}}\,(1)]\) \( = 2 \times {10^{ - 11}}{\rm{s}}\)
KCET - 2011
PHXII09:RAY OPTICS AND OPTICAL INSTRUMENTS
364987
Assertion : The colour of the green flower seen through red glass appears to be dark. Reason : Red glass transmits only red light.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
Red glass transmits only red (and absorbs other colors). The green light from green flower is absorbed by red glass and so the flower appears to be black. So correct option is (1).
364983
A point source of light is kept below the surface of water \(\left( {{n_w} = \frac{4}{3}} \right)\) at a depth of \(\sqrt 7 m\) . The radius of the circular bright patch of light noticed on the surface of water is ........ \(m\)
1 \(\frac{3}{{\sqrt 7 }}\)
2 3
3 \(\frac{{\sqrt 7 }}{3}\)
4 \(\sqrt 7 \)
Explanation:
Here, Refractive index of water, \({n_w} = \frac{4}{3}\) \(\therefore \;\;\sin C = \frac{1}{{{n_w}}} = \frac{1}{{\left( {\frac{4}{3}} \right)}} = \frac{3}{4}\,\,\,\,[C = critical\,\,angle]\) \( \Rightarrow \tan C = \frac{3}{{\sqrt {{4^2} - {3^2}} }} = \frac{3}{{\sqrt 7 }}\;\;\;\;\;\;(1)\) From figure, \(\tan C = \frac{R}{{\sqrt 7 }}\;\;\;\;\;\;(2)\) Equating (1) and (2) , we get \(\frac{3}{{\sqrt 7 }} = \frac{R}{{\sqrt 7 }} \Rightarrow R = 3\;{\mkern 1mu} m\)
KCET - 2012
PHXII09:RAY OPTICS AND OPTICAL INSTRUMENTS
364984
The refractive index of water is 1.33 . The direction in which a man under water should look to see the setting sun is
364985
The main cause of decrease in intensity of light on refraction is
1 Scattering of light
2 Passing of light from one medium to another
3 Total internal reflection
4 Partial reflection and partial absorption
Explanation:
Conceptual Question
PHXII09:RAY OPTICS AND OPTICAL INSTRUMENTS
364986
The time required for the light to pass through a glass slab (refractive index = 1.5) of thickness \(4\;mm\) is ( \(c = 3 \times {10^8}m{s^{ - 1}}\), speed of light in free space)
1 \({10^{ - 11}}\sec \)
2 \(2 \times {10^{ - 11}}\sec \)
3 \(2 \times {10^{ + 11}}\sec \)
4 \(2 \times {10^{ - 5}}\sec \)
Explanation:
Speed of light in glass slab is \(v = \frac{c}{\mu } = \frac{{3 \times {{10}^8}}}{{1.5}}m{s^{ - 1}}\;\;\;\;\;\;(1)\) The time required for the light to pass through a glass slab of thickness \(4\;mm\) is \(t = \frac{{{\rm{thickness}}}}{{{\rm{velocity}}\left( v \right)}} = \frac{{4 \times {{10}^{ - 3}}m}}{{\frac{{3 \times {{10}^8}m{s^{ - 1}}}}{{1.5}}}}\,\,\,[{\rm{using}}\,(1)]\) \( = 2 \times {10^{ - 11}}{\rm{s}}\)
KCET - 2011
PHXII09:RAY OPTICS AND OPTICAL INSTRUMENTS
364987
Assertion : The colour of the green flower seen through red glass appears to be dark. Reason : Red glass transmits only red light.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
Red glass transmits only red (and absorbs other colors). The green light from green flower is absorbed by red glass and so the flower appears to be black. So correct option is (1).
