8th Standard CBSE Syllabus & Materials
8th Standard CBSE
CBSE 8th Social Science Theme D - Factors of Production - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Social Science Theme C - Universal Franchise and India's Electoral System - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Social Science Theme B - The Rise of the Marathas - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Social Science Theme B - Reshaping India's Political Map - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Social Science Theme A - Natural Resources and Their Use - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Science Keeping Time with Skies - New Model Questions Papers Study Material - QB365 Set A
Published on: 01/01/2019
8th Std Revision Test
Download CBSE Class 8th Standard CBSE Science question papers, sample papers, important questions, and previous year solved papers in PDF format. Get free study materials, NCERT solutions, and exam preparation resources for Class 8th Standard CBSE Science
Questions + Answers key
Take MCQ Science Test
1.
What is earthing? What is its importance?
2.
In 'tug of war' when two teams pull equally hard, then what happens?
3.
What are the disadvantages of using wood as a fuel?
4.
If a metal coin is dropped on hard floor, it produces a ringing sound. What is this property of metals known as?
5.
You must have seen the farmer plough seedlings of paddy into the field from a nursery. Give the name of this process
6.
Air at a place is said to be polluted. What does it mean? Give the composition of air around us.
7.
AIDS is one of the most deadly diseases, the world is fighting with. What is AIDS? Name the causal agent and the ways through which its transmitted.
8.
Write the name of the products obtained when coal is heated strongly in the absence of air. Write the name of this process also.
9.
Ankur's mother told him to wash his hands with soap before eating because his hands might have bacteria. Ankur did not believe her because he could not see anything on his hands. Why couldn't Ankur see the bacteria on his hands? State how bacteria can be harmful to humans.
10.
The jelly-like fluid substance present in cells is called
protoplasm
chloroplast
chromosome
cytoplasm
11.
Coal-tar contains about _______ substances:
400
300
100
200
12.
Highest percentage of air consists of
oxygen
carbon dioxide
nitrogen
argon
13.
The sun appears to move from east to west around the Earth. This means that earth rotates from
east to west
west to east
north to south
west to north
14.
Given below are events that lead to pregnancy and development of embryo.
(i) Fertilisation of egg,
(ii) Maturation of egg
(iii) Release of egg
(iv) Embedding of embryo in uterus
Which of the following options gives the correct order of sequence in which they occur?
(i), (ii), (iii), (iv)
(ii), (i), (iii), (iv)
(i), (iv), (ii), (iii)
(ii), (iii), (i), (iv)
15.
Two objects repel each other. This repulsion could be due to
frictional force
electrostatic force
magnetic force
either a magnetic or an electrostatic force
16.
In order to reduce the loudness of a sound, we have to
decrease its frequency of vibration of the sound
increase its frequency of vibration of the sound
decrease its amplitude of vibration of the sound
increase its amplitude of vibration of the sound
17.
Which of the following is not likely to cause tsunami?
A major nuclear explosion under sea
Earthquake
Volcanic eruption
Lightning
18.
Which of the following is very hard?
Copper
Sodium
Potassium
Coal
19.
Weeds are the
main crop plants
insects and pests
unwanted plants growing along the crop
chemical substances
20.
In the following statements. the underlined words are jumbled up. Write them in their correct form.
(i) Air contains 78% ginroten and 21% gonexy.
(ii) Vehicles produce high level of pollutants like carbon dioxide, nitrogen oxides, nobrac moondexi and mosek.
(iii) Carbon dioxide, thaneme, nitrous oxide and water vapour are known as heengrouse sega.
(iv) Gangotri glacier in Himalaya has started melting because of lablog ringwam.
(v) Whenever harmful substances such as wages, toxic chemicals, silt, etc. get mixed with water, the water becomes potdulled.
21.
Explain the position and functions of nucleus in a cell
22.
In physics class teacher ask to his student that a man carrying a load of 50 N in his hand pulling it. The area of palm where the load act is 5 cm2. Then
(a) Determine the pressure acting on the fingers of man.
(b) Also, find the pressure acting if the man carrying the same load by keeping it on the shoulder occupying an area of 50 cm2.
(c) Mention the type of teaching skill of teacher is being represented here?
23.
Kanika switched ON the television to listen to her favourate movie. After sometime, she heard a loudspeaker sound coming from her neighbour house. Then, she switched OFF the television and closed her ears so that loudspeaker sound should not enter to her ears.
(a) State the type of sound coming from the television.
(b) Explain how Kanika were able to distinguish the category of sound.
(c) Mention whether the sound coming from TV and loudspeaker was audible or inaudible.
(d) Give the value displayed by Kanika here
24.
The substance A is a fossil fuel. It occurs deep below the earth's crust in certain areas. Another fossil fuel B is found above the substance A. When A is subjected to a process C, a number of different products (fractions) are collected at different temperature ranges which have different uses. A special grade of product D obtained in this process is used as aviation fuel in jet aeroplanes. The product D is also used in stoves, lamps, etc
Now give the answer of the following questions.
(a) What are the substances, A and B?
(b) Write the physical states of substances A and B.
(c) What is the process C called?
(d) Name the product D.
25.
Give causative microorganism, mode of transmission and one preventive measure Qf human diseases like Polio, Cholera and Hepatitis-B.
26.
Thyroxine
27.
Structural unit of organism
28.
Record of animals and plants
29.
Sulphur
30.
Tuberculosis
31.
_________________are groups of stars that appear to form recognizable shapes
32.
Identify the organism given below. Where does it reproduce?
33.
______ and ________ are the examples of Rabi crops.
34.
Ball bearings reduce friction because they rolls rather than ___________
35.
The electrical Charge generated by rubbing two objects is ____________.
36.
The friction force on an object in a fluid depends only on its speed.
37.
We should not wear synthetic clothes while cooking in the kitchen or in a laboratory.
38.
Water fit for drinking is potable water.
39.
A new human individual develops from a cell called gamete.
40.
Higher the amplitude of vibration, lesser is the pitch.
41.
What are multiple images?
42.
Who organized 'Say no to cracker' campaign?
43.
What do you mean by metamorphosis?
44.
On what factor does force of friction depend?
45.
On which factor does loudness of sound depend?
46.
What is static electricity?
47.
A human cell that can change shape.
48.
What is biodiversity?
49.
Define cellulose.
50.
What are the main tools used for agriculture practices?
1.
The process of transferring of charge from a charged object to the earth is called earthing. It is provided in buildings to protect us from electrical shocks due to any leakage of electric current.
2.
In 'tug of war', when two teams pull equally hard, then the rope does not move in any direction.
3.
It has low calorific value and causes a lot of pollution.
4.
The property of metals to produce ringing sound is called sonority.
5.
The process of transferring the seedings from the nursery to the main field by hand or manually is called seed transplantation.
6.
This means that air is contaminated by the addition of unwanted and harmful substances which are injurious to living organisms, property or interferes with normal environmental processes. This is called air pollution. The air around us is a mixture of various gases. It is composed of 78% nitrogen,21% oxygen and remaining 1% by CO2,Ar CH4, O3 and water vapour.
7.
AIDS is Acquired Immunodeficiency Syndrome.
It is a disease caused by HIV (Human Immunodeficiency Virus). The AIDS virus can easily pass from an injected person to a healthy person through ways given below:
(i) Sharing the syringes for injecting drugs.
(ii) Unprotected sex with an infected person.
(iii) Transfusion of blood into a healthy person from an infected person.
(iv) Through milk from an infected mother to an infant.
8.
When coal is heated strongly in the absence of air in closed retorts, various useful products are obtained. These are coke, coal tar and coal gas. The strong heating of coal in the absence of air is called destructive distillation of coal.
9.
Bacteria are too small, cannot be seen with the naked eye. It can be seen only with a microscope.That's why Ankur could not see the bacteria on his hands. Bacteria can cause various diseases like dysentry, typhoid, cholera, etc.
10.
(d)
cytoplasm
11.
(d)
200
12.
(c)
nitrogen
13.
(b)
west to east
14.
(d)
(ii), (iii), (i), (iv)
15.
(d)
either a magnetic or an electrostatic force
16.
(c)
decrease its amplitude of vibration of the sound
17.
(d)
Lightning
18.
(b)
Sodium
19.
(c)
unwanted plants growing along the crop
20.
(i) Nitrogen, oxygen.
(ii) Carbon monoxide, smoke
(iii) Methane, green house gases.
(iv) Global warming.
(v) Sewage, Polluted
21.
Nucleus is the most important component of the living cell. It is round or spherical in shape and situated in the centre of the cell. Nucleus is separated from cytoplasm by a membrane called nuclear membrane. This membrane is porous and allows the movement of materials between the cytoplasm and inner side of the nucleus. There is a small and spherical body in the nucleus. It is called nucleolus. Nucleus contains thread-like structures called chromosomes. These carry genes and help in inheritance or transfer of characters from the parents to the offspring. Nucleus also acts as a control centre of the activities of the cell.
22.
(a) Here, F = 50N, A = 5 cm2 = 5 x10-4 m2
\(\therefore p=\frac{F}{A}=\frac{50}{5\times10^{-4}}=10^{5}\) Pa
(b) Here, area changes to 50 cm2= 50 x 10-4 m2
\(\therefore p=\frac{F}{A}=\frac{50}{5\times10^{-4}}=10^{4}\)Pa
(c) Here the values displayed by the teacher is the experience and his ideality.
23.
(a) The sound of the music was coming from the television.
(b) She realised after hearing both the sounds that the sound coming from TV is music and enjoyable and that coming from outside loudspeaker is noisy and painful.
(c) The sound coming from TV and loudspeakers was in audible range, i.e. 20 Hz to 20 kHz.
(d) The value displayed by Kanika is attraction towards music and hate with the loudspeakers.
24.
(a) A is petroleum and B is natural gas.
(b) A is thick liquid while B is gas.
(c) C is called fractional distillation
(d) D is kerosene.
25.
| Disease | Causative microorganism | Mode of transmission | Preventive measure |
| Polio | Virus | Air/Water | Vaccination should be given at suitable age |
| Cholera | Bacteria | Water/Food | Maintain personal hygiene and good sanitary habits. |
| HepatitisB | Virus | Water | Drink boiled drinking water and proper vaccination should be taken. |
26.
( )
Goitre
27.
( )
Cel
28.
( )
Red Data Book
29.
( )
For making crackers
30.
( )
Bacteria
31.
( )
Constellations
32.
( )
Virus. It reproduces in the host cell.
33.
( )
Wheat, gram
34.
( )
slide
35.
( )
static electricity
36.
(b)
37.
(a)
38.
(a)
39.
(b)
40.
(b)
41.
( )
Images formed by mirrors placed at an angle to one another are called multiple images.
42.
( )
Children from many schools organized "Sayno to cracker" to reduce air pollution during Diwali.
43.
( )
The change from larva to an adult is called metamorphosis
44.
( )
Contact surface.
45.
( )
The loudness of sound depends on the amplitude.
46.
( )
The electricity generated by rubbing is called static electricity.
47.
( )
White Blood Cell
48.
( )
Biodiversity refers to the variety of organisms existing on the earth, their inter-relationships and relationships with the environment.
49.
( )
Cellulose is made up of a large number of glucose units.
50.
( )
The main tools are plough, hoe and cultivator.
8th Standard CBSE Syllabus & Materials
8th Standard CBSE
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CBSE 8th Standard CBSE Subjects
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