Weeds are the

1

(a)

main crop plants

(b)

insects and pests

(c)

unwanted plants growing along the crop

(d)

chemical substances

Which of the following is very hard?

1

(a)

Copper

(b)

Sodium

(c)

Potassium

(d)

Coal

Coal-tar contains about _______ substances:

1

(a)

400

(b)

300

(c)

100

(d)

200

The jelly-like fluid substance present in cells is called

1

(a)

protoplasm

(b)

chloroplast

(c)

chromosome

(d)

cytoplasm

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?

1

(a)

(i), (ii), (iii), (iv)

(b)

(ii), (i), (iii), (iv)

(c)

(i), (iv), (ii), (iii)

(d)

(ii), (iii), (i), (iv)

Two objects repel each other. This repulsion could be due to

1

(a)

frictional force

(b)

electrostatic force

(c)

magnetic force

(d)

either a magnetic or an electrostatic force

In order to reduce the loudness of a sound, we have to

1

(a)

decrease its frequency of vibration of the sound

(b)

increase its frequency of vibration of the sound

(c)

decrease its amplitude of vibration of the sound

(d)

increase its amplitude of vibration of the sound

Which of the following is not likely to cause tsunami?

1

(a)

A major nuclear explosion under sea

(b)

Earthquake

(c)

Volcanic eruption

(d)

Lightning

The sun appears to move from east to west around the Earth. This means that earth rotates from

1

(a)

east to west

(b)

west to east

(c)

north to south

(d)

west to north

Highest percentage of air consists of

1

(a)

oxygen

(b)

carbon dioxide

(c)

nitrogen

(d)

argon

______ and ________ are the examples of Rabi crops.

1

(a)

Wheat, gram

Identify the organism given below. Where does it reproduce?

1

(a)

Virus. It reproduces in the host cell.

Ball bearings reduce friction because they rolls rather than ___________

1

(a)

slide

The electrical Charge generated by rubbing two objects is ____________.

1

(a)

static electricity

_________________are groups of stars that appear to form recognizable shapes

1

(a)

Constellations

We should not wear synthetic clothes while cooking in the kitchen or in a laboratory.

1

(a) False

(b) True

A new human individual develops from a cell called gamete.

1

(a) True

(b) False

The friction force on an object in a fluid depends only on its speed.

1

(a) True

(b) False

Higher the amplitude of vibration, lesser is the pitch.

1

(a) True

(b) False

Water fit for drinking is potable water.

1

(a) False

(b) True

What are the main tools used for agriculture practices?

1

(a)

The main tools are plough, hoe and cultivator.

Define cellulose.

1

(a)

Cellulose is made up of a large number of glucose units.

What is biodiversity?

1

(a)

Biodiversity refers to the variety of organisms existing on the earth, their inter-relationships and relationships with the environment.

A human cell that can change shape.

1

(a)

White Blood Cell

What do you mean by metamorphosis?

1

(a)

The change from larva to an adult is called metamorphosis

On what factor does force of friction depend?

2

(a)

Contact surface.

On which factor does loudness of sound depend?

2

(a)

The loudness of sound depends on the amplitude.

What is static electricity?

2

(a)

The electricity generated by rubbing is called static electricity.

What are multiple images?

2

(a)

Images formed by mirrors placed at an angle to one another are called multiple images.

Who organized 'Say no to cracker' campaign?

2

(a)

Children from many schools organized "Sayno to cracker" to reduce air pollution during Diwali.

You must have seen the farmer plough seedlings of paddy into the field from a nursery. Give the name of this process

2

(a)

If a metal coin is dropped on hard floor, it produces a ringing sound. What is this property of metals known as?

2

(a)

What are the disadvantages of using wood as a fuel?

2

(a)

In 'tug of war' when two teams pull equally hard, then what happens?

2

(a)

What is earthing? What is its importance?

2

(a)

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.

5

(a)

Write the name of the products obtained when coal is heated strongly in the absence of air. Write the name of this process also.

5

(a)

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.

5

(a)

What is the cause of friction?

5

(a)

Air at a place is said to be polluted. What does it mean? Give the composition of air around us.

5

(a)

Give causative microorganism, mode of transmission and one preventive measure Qf human diseases like Polio, Cholera and Hepatitis-B.

5

(a)

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.

5

(a)

Explain the position and functions of nucleus in a cell

5

(a)

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?

5

(a)

1. 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

   5

   (a)

2. 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.

   5

   (a)