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: 16/06/2021
QB365 provides detailed and simple solution for every Book back Questions in class 8 Science Subject. It will helps to get more idea about question pattern in every book back questions with solution.
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.
The radius of curvature of a spherical mirror is 20 cm. Find its focal length.
2.
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.
3.
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.
4.
If two plane mirrors are inclined to each other at an angle of 90°, find the number of images formed.
5.
Focal length of a spherical mirror is 7 cm. What is its radius of curvature?
1.
Radius of curvature = 20 cm
Focal length (f) =\(\frac { Radius\quad of\quad curvat }{ 2 } \)
=\(\frac { R }{ 2 } =\frac { 20 }{ 2 } \)=10 cm
2.
wμg = \(\frac { Refractive\ index\ of\ glass }{ Refractive\ index\ of\ water } \)
\(=\frac { \frac { 3 }{ 2 } }{ \frac { 4 }{ 3 } } =\frac { 9 }{ 8 } \)=1.125
3.
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
4.
Angle of inclination = 90°
Number of images for=\(\frac { { 360 }^{ 0 } }{ \theta } -1=\frac { { 360 }^{ 0 } }{ { 90 }^{ 0 } }\)-1=4-1=3
5.
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
