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: 19/08/2019
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 unit for surface tension is _________
Nm
N-1m
N-1m-1
Nm-1
2.
Based on shape, the bacteria are classified into _______ types.
2
3
4
5
3.
Limestone contains ______ mainly.
Calcium chloride
calcium carbonate
calcium nitrate
calcium sulphate
4.
Burning of paper is a______ change.
Physical
chemical
physical & chemical
neutral
5.
The liquid metal used in thermometers is
Copper
Mercury
Silver
Gold
6.
SI unit stands for
International system of units
Integrated System of units
International symbol of units
Integrated symbol of units
7.
__________ is the best reflector of light
8.
The book “Genera Plantarum” was written by _________
9.
______ is the basic material to manufacture urea.
10.
A simple barometer was first constructed by _____.
11.
_______ is used to measure electric current.
12.
The dominant phase of the pteridophytes is diploid(2n).
13.
All bryophytes are hydrophytes.
14.
Citrus canker is transmitted by insects.
15.
Rolling friction is slightly greater than the sliding friction.
16.
If One coulomb of charge flowing in one minute, it is called ‘ampere’.
17.
Assertion (A): Clinical thermometers are graduated in fahrenheit scale.
Reason (R): Weather reports are given in celsius scael
a) If both assertion and reason are true but reason is the correct explanation of the assertion.
b) If both assertion and reason are true but reason is not the correct explanation of the assertion.
c) Assertion is true but reason is false.
d) Assertion is false, but reason is true.
18.
Assertion(A): Bryophytes are called Amphibians of the plant kingdom.
Reason(R): Bryophytes are land plants but they need water for the completion of their life cycle.
a) A correct R correct
b) A incorrect R correct
c) A and R correct R explain A
d) A and R incorrect
19.
Assertion: The SI system of units is the suitable system for measurements.
Reason: The SI unit of temperature is Kelvin.
a. Both assertion and reason are true and reason is the correct explanation of the assertion.
b. Both assertion and reason are true but reason is not the correct explanation of the assertion.
c. Assertion is true, but reason is false.
d. Both assertion and reason are false.
20.
State the laws of reflection.
21.
Mention any three ways of minimising friction.
22.
Define- Temperature.
23.
Hardware
24.
Edward Jenner
25.
Compound
26.
Snell’s law
27.
Lubricants
28.
Differentiate between Osmoconformers and Osmoregulators?
29.
Who discovered penicillin?
30.
What is pollution?
31.
Differentiate between inhalation and exhalation.
32.
Explain the three types of pollution.
33.
Focal length of a spherical mirror is 7 cm. What is its radius of curvature?
34.
Convert 60° into radian.
35.
Iron in water and air: Brown colour :: Iron in copper sulphate solution:_________
36.
Mercury: liquid metal_________liquid non-metal
1.
(d)
Nm-1
2.
(c)
4
3.
(b)
calcium carbonate
4.
(b)
chemical
5.
(b)
Mercury
6.
(a)
International system of units
7.
( )
Silver
8.
( )
Bentham and Hooker
9.
( )
Ammonia
10.
( )
Torricelli
11.
( )
Ammeter
12.
(a)
13.
(b)
14.
(b)
15.
(b)
16.
(b)
17.
b) If both assertion and reason are true but reason is not the correct explanation of the assertion.
18.
c) A and R correct R explain A
19.
b. Both assertion and reason are true but reason is not the correct explanation of the assertion.
20.
i) The incident ray, the reflected ray and the normal at the point of incidence, all lie in the same plane.
ii) The angle of incidence and the angle of reflection are always equal.
21.
Ways to minimise friction
(i) By applying lubricants like grease and cocount oil.
(ii) By using ball bearing we can change sliding friction to rolling friction
(ii) By smoothening the surface of contact of the moving bodies rather than irregular surfaces.
22.
Measure of the average kinetic energy of the particles in a system.
23.
RAM
24.
Vaccine
25.
Atoms of different kinds
26.
sin i /sin r = μ
27.
reduce friction
28.
| Osmoconformers | Osmoregulators |
|---|---|
| Osmoconformers try to maintain the osmolality of their body matching with their surroundings. eg: Most of the invertebrates, marine organisms |
Organisms maintain their internal osmolaliry which canbe extremely different from that of the surrounding environment, through physiological processes. eg: Human |
29.
Sir Alexander Fleming discovered penicillin
30.
Any unwanted change in physical, chemical and biological properties of the environment is termed as pollution.
31.
| S.No | Inhalation | Exhalation |
|---|---|---|
| 1. | The muscles of the diaphragm | The muscles of the diaphram relax. |
| 2. | The diaphram goes downward. | The diaphram goes upwards |
| 3. | The ribs move upwards and outwards. | The ribs move downwards. |
| 4. | The volume of thoracic cavity increases. | the volume of thoracic cavity decreases. |
| 5. | air enteres the lungs through the nose | Air goes out of the lungs through the nose. |
32.
| S.No | Type of pollution | Chemical substances responsible for the pollution | Effects |
|---|---|---|---|
| 1 | Air pollution | Carbon dioxide, Carbon monoxide, oxides of sulphur, oxides of nitrogen, Chlorofluorocarbons, methane etc. | Acid rain, Global warming, respiratory problems etc |
| 2 | Water pollution | Wastewater containing chemical substances (eg. dyeing industries), detergents, oil spillage etc. | Decrease in quality of water, skin diseases etc |
| 3 | Land pollution | Fertilizers like urea, various pesticides, herbicides etc | Spoilage of land, cancer, respiratory diseases etc. |
33.
Radius of curvature (R) = 2 × focal length
= 2 × 7 = 14 cm
34.
We know that,
I0 =\(\frac { \pi }{ 180 } \)
=\(\frac { \pi }{ 3 } \) radian
35.
Green colour
36.
Bromine
8th Standard Syllabus & Materials
8th Standard
TN 8th Tamil இயல் 3 - கல்வி கரையில - பாடறிந்து ஒழுகுதல் Important Questions And Answers Study Material - QB365 Set A
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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
