8th Standard Syllabus & Materials
8th Standard
TN 8th Tamil இயல் 3 - கல்வி கரையில - வினைமுற்று Important Questions And Answers Study Material - QB365 Set A
NEW8th Standard
TN 8th Tamil இயல் 2 - ஈடில்லா இயற்கை - மயங்கொலிகள் Important Questions And Answers Study Material - QB365 Set A
NEW8th Standard
TN 8th Tamil இயல் 2 - ஈடில்லா இயற்கை -பட்டமரம் Important Questions And Answers Study Material - QB365 Set A
NEW8th Standard
TN 8th Tamil இயல் 2 - ஈடில்லா இயற்கை - இயற்கையை போற்றுவோம் Important Questions And Answers Study Material - QB365 Set A
NEW8th Standard
TN 8th Tamil இயல் 1 - தமிழ் இன்பம் - ஆழிக்கு இணை Important Questions And Answers Study Material - QB365 Set A
NEW8th Standard
TN 8th Tamil இயல் 2-ஈடில்லா இயற்கை - திருக்குறள் Important Questions And Answers Study Material - QB365 Set A
Published on: 18/09/2019
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Download Tamil Nadu 8th Standard Science question papers, model tests, one-mark questions, important questions, and public exam papers in PDF format. Free study materials and answer keys for TN State Board students.
Questions + Answers key
Take MCQ Science Test1.
When will the concave mirror form a real and inverted image?
2.
What is the value of velocity of light in air?
3.
Who founded the Book "On Burning Mirrors"?
4.
Who constructed first parabolic mirrors in the form of reflector?
5.
Which mirror is used in solar cookers and solar water heaters?
6.
The radius of curvature of a spherical mirror is 20 cm. Find its focal length.
7.
Refractive index of water is 4/3 and the refractive index of glass is 3/2. Find the refractive index of glass with respect to the refractive index of water.
8.
Speed of light in air is 3 × 108 ms-1 and the speed of light in a medium is 2 × 108 ms-1. Find the refractive index of the medium with respect to air.
9.
If two plane mirrors are inclined to each other at an angle of 90°, find the number of images formed.
10.
Focal length of a spherical mirror is 7 cm. What is its radius of curvature?
1.
Object should be placed between focus and pole of the mirror.
2.
3 x 108 ms-1
3.
Mathematician Diodes.
4.
Heinrich Hertz.
5.
Parabolic mirror.
6.
Radius of curvature = 20 cm
Focal length (f) =\(\frac { Radius\quad of\quad curvat }{ 2 } \)
=\(\frac { R }{ 2 } =\frac { 20 }{ 2 } \)=10 cm
7.
wμg = \(\frac { Refractive\ index\ of\ glass }{ Refractive\ index\ of\ water } \)
\(=\frac { \frac { 3 }{ 2 } }{ \frac { 4 }{ 3 } } =\frac { 9 }{ 8 } \)=1.125
8.
Refractive index (μ) =\(\frac { Speed\ of\ light\ in\ air\ (c) }{ Speed\ of\ light\ in\ the\ medium(v) } \)
μ =\(\frac { 3\times { 10 }^{ 8 } }{ 2\times { 10 }^{ 8 } } \)=1.5
9.
Angle of inclination = 90°
Number of images for=\(\frac { { 360 }^{ 0 } }{ \theta } -1=\frac { { 360 }^{ 0 } }{ { 90 }^{ 0 } }\)-1=4-1=3
10.
Radius of curvature (R) = 2 × focal length
= 2 × 7 = 14 cm
8th Standard Syllabus & Materials
8th Standard
TN 8th Tamil இயல் 3 - கல்வி கரையில - பாடறிந்து ஒழுகுதல் Important Questions And Answers Study Material - QB365 Set A
NEW8th Standard
TN 8th Tamil இயல் 3-கல்வி கரையில - பல்துறைக் கல்வி Important Questions And Answers Study Material - QB365 Set A
NEW8th Standard
TN 8th Tamil இயல் 3-கல்வி கரையில - புத்தியைத் தீட்டு Important Questions And Answers Study Material - QB365 Set A
NEW8th Standard
TN 8th Tamil இயல் 2 - ஈடில்லா இயற்கை - தமிழர் மருத்துவம் ( நேர்காணல்) Important Questions And Answers Study Material - QB365 Set A
Tamilnadu Stateboard 8th Standard Subjects
Tamilnadu Stateboard Standards
