Which of the following is not a traditional method of irrigation?

The following is an antibiotic

Which is not a property of plastic?

Boojho has learnt that non-metals on beating with a hammer are generally broken into pieces.Which of the following is non-metal?

Purest form of carbon is

The product(s) of combustion is/are

The Siberian crane comes to India every year in winter for a few months. 

Choose the correct statements.

Sets of reproductive terms are given below. Choose the set that has an incorrect combination.

The most conspicuous visible change that occurs in boys during puberty is

During dry weather while combing hair, sometimes we experience hair flying apart. The force responsible for this is

A toy car released with the same initial speed will travel farthest on

Ultrasound has frequency of vibration

Which of the following solutions will not make the bulb glow in figure?

When a glass rod is rubbed with a piece of silk cloth, the rod

A small hole P is made in a piece of cardboard. The hole is illuminated by a torch as shown in figure. The pencil of light coming out of the hole falls on a mirror. At which point should the eye be placed so that the hole can be seen?

Which star is nearest to the Earth?

The type of pollution which is likely to affect Taj Mahal in Agra to a greater extent is

One day Paheli saw her mother put some gram seeds in a vessel and pour some water on them. After a few minutes some seeds started to float on the top. She wondered why some seeds floated on water?

In the soil, which nutrient is enriched by blue-green algae (cyanobacteria)?

Name five articles made from nylon.

In the figure, iron nail is replaced by a wooden stick, will the bulb glow or not? Justify your answer.

We use all our natural resources forever. Can it be possible?

Which poisonous gas is formed as a result of incomplete combustion?

Why is it important to conserve forests?

Make a sketch of the human nerve cell. What function do nerve cells perform?.

Draw a labelled diagram of human ovum

What are the drawbacks of adolescent pregnancy?

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

Can we reduce friction to zero by polishing surfaces or using large amount of lubricants?

Explain in brief about musical sound.

Does distilled water conduct electricity?

Boojho wonders why they took so many years to realise the similarity.

Black objects appear black. Why?

In the given figure, out of the positions A, B, C and D which will indicate the position of the sun. Draw the sun at the appropriate position.

The use of excessive fertilisers and pesticides leads to the deficiency of an important substance in water. Name the substance.

What are the disadvantages of fertilizers?

What are antibiotics? What precautions must be taken while taking antibiotics?

A bucket made up of plastic does not rust like a bucket made up of iron. Why?

Saloni took a piece of burning charcoal and collected the gas evolved in a test tube.
(a) How will she find the nature of the gas?
(b) Write down word equations of all the reactions taking place in this process.

Nikita visited a thermal power plant. She was surprised to see the use of tonnes of coal per day to generate electricity. She was highly disturbed when she thought of all the coal getting exhausted in one day. She decided from that day to use only required amount of electricity without any wastage and spread the message across.
Read the given passage and answer the following questions
(a) What role does coal play in a thermal power plant?
(b) What values are possessed by Nikita?

Give reasons.
(a) Water is not used to control fires involving electrical equipments.
(b) LPG is a better domestic fuel than wood.
(c) Paper by itself catches fire easily, whereas a piece of paper wrapped around an aluminium pipe does not.

A new species X is introduced in a forest. How is it likely to affect the local species of that area?

Outline the structural hierarchy that is found in all organisms.

It is necessary to produce large number of eggs and sperms by the animals which reproduce by external fertilisation. Why?

In human females, each time during maturation and release of egg, the inner wall of uterus thickness. Is this thickening permanent? Give reasons.

Does the force of gravitation exist between two astronauts in space?

Suppose your writing desk is tilted a little. A book kept on it starts sliding down. Show the direction of frictional force acting on it.

What is hearing impairment? How do people over come this problem?

Last Monday, Ankush woke up late in the morning. So, he saw the time and suddenly realised that he had got late for an interview, which he was supposed to give after reaching the venue by the right time. Immediately, he turned on the geyser but it did not work. He got more tensed, then he used an electric iron rod through which he could get some boiled water for his bath. Actually, there was an earthing problem in the switch board about which he was unawared of. He was barefooted and was just about to switch on the electric iron rod but at the same he got restricted to do so by one his room partner living with him. It could be dangerous for Ankush.
(a) Explain in brief that what could be happened with Ankush, if he switched on the electric iron rod (without wearing any slippers in his foot).
(b) Mention, the values showed by Ankush's friend

If the materials used for constructing a building were good conductors, do you think lightning will strike the building? Will the lightning conductor be still required to be installed in the building?

Explain how do we see various objects.

Explain how the Earth rotates on a tilted axis.

Prepare a brief speech on global warming. You have to deliver the speech in your class.

What is irrigation? Describe two methods of irrigation which conserve water.

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

Nikita's mother went to the market to buy new lunch box for Nikita. She saw different lunch boxes made up of plastics as well as steel. Plastics lunch boxes of different colours was very attractive but the steel lunch box was very simple. Nikita's mother told him to select a lunch box for you. She selected a lunch box made of steel instead of plastic one. Her mother purchased the steel lunch box for him.
Read te following passage and answer the following questions.
(a) Why Nikita prefer steel lunch box instead of plastic one?
(b) Is plastic materials environment friendly? Explain.
(c) What values are shown by Nikita?

Write the difference between metals and nonmetals on the basis of their physical properties.

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.

Explain the harmful effects of burning fuels.

How does deforestation lead to desertification?

Explain the position and functions of nucleus in a cell

Observe the following figures.

(i) Identify the stages (a) to (d) in figure during development of human baby.
(ii) Arrange the stages in correct sequence of development.
(iii) Explain the development that takes place in anyone stage.

The table below shows the data on likely heights of boys and girls as they grow in age. Draw graphs showing height and age for both boys and girls on the same graph paper. What conclusions can be drawn from these graphs?

What are contact and non-contact forces? Explain briefly with suitable examples.

Explain with the help of an example that heat is produced by friction.

Sketch larynx and explain its function in your own words

Observe the circuit given in figure.

Boojho set up this circuit for purification of copper. What will be the nature of
(a) plate A
(b) plate B
(c) and the solution. Explain the process of purification

Explain protection against earthquake.

How is the phenomenon of reflection used in making a kaleidoscope? What are the applications of a kaleidoscope?

Across:
(i) Groups of stars
(iii) A use of artificial satellite

Down:
(ii) Constellation with seven stars looking like questions mark.
(iv) The other name of Milky way.

How does air get polluted? Explain.