Match items in column A with one or more items in column B:
A B
(i) Inner planets (a) Saturn
(ii) Outer planets (b) Pole Star
(iii) Constellation (c) Great Bear
(iv) Satellite of the Earth (d) Moon
(e) Earth
(f) Orion
(g) Mars
A B
(i) Inner planets (a) Saturn
(ii) Outer planets (b) Pole star
(iii) Constellation (c) Great Bear, (f) Orion
(iv) Satellite of the Earth (d) Moon
What is a constellation? Name any two constellations.
Explain how you can locate the Pole Star with the help of Ursa Major.
Boojho made the following sketch (Fig. 17.29) of the solar system. Is the sketch correct? If not, correct it.
Draw sketches to show the relative positions of prominent stars in
(a) Ursa Major and (b) Orion
Name two objects other than planets which are members of the solar system.
Why is the distance between stars expressed in light years? What do you understand by the statement that a star is eight light years away from the Earth?
The radius of Jupiter is 11 times the radius of the Earth. Calculate the ratio of the volumes of Jupiter and the Earth. How many Earths can Jupiter accomodate?
Phases of the moon occur because
(a) we can see only that part of the moon which reflects light towards us.
(b) our distance from the moon keeps changing.
(c) the shadow of the Earth covers only a part of moon’s surface.
(d) the thickness of the moon’s atmosphere is not constant.
Do all the stars in the sky move? Explain.
Mark the following statements as true (T) or false (F):
(a) Pole Star is a member of the solar system. ( )
(b) Mercury is the smallest planet of the solar system. ( )
(c) Uranus is the farthest planet in the solar system. ( )
(d) INSAT is an artificial satellite. ( )
(e) There are nine planets in the solar system. ( )
(f) Constellation Orion can be seen only with a telescope. ( )
Which of the following can be beaten into thin sheets?
(a) Zinc (b) Phosphorus (c) Sulphur (d) Oxygen
Fill in the blanks
(a) Most liquids that conduct electricity are solutions of , ______________ and ______________.
(b) The passage of an electric current through a solution causes ______________ effects.
(c) If you pass current through copper sulphate solution, copper gets deposited on the plate connected to the terminal of the battery.
(d) The process of depositing a layer ofany desired metal on another material by means of electricity is called .
Give two examples each of situations in which you push or pull to change the state of motion of objects.
Fill in the blanks:
(a) Friction opposes the _____________ between the surfaces in contact with each other.
(b) Friction depends on the _____________ of surfaces. (c) Friction produces __________.
(d) Sprinkling of powder on the carrom board ________ friction.
(e) Sliding friction is ___________ than the static friction.
List conditions under which combustion can take place.
Indicate whether the following statements are True (T) or False (F).
(a) Unicellular organisms have one-celled body. (T/F)
(b) Muscle cells are branched. (T/F)
(c) The basic living unit of an organism is an organ. (T/F)
(d) Amoeba has irregular shape. (T/F)
Which of the following cannot be charged easily by friction?
(a) A plastic scale
(b) A copper rod
(c) An inflated balloon
(d) A woollen cloth.
Fill in the blanks:
(a) A place where animals are protected in their natural habitat is called .
(b) Species found only in a particular area is known as .
(c) Migratory birds fly to far away places because of changes.
Suppose you are in a dark room. Can you see objects in the room? Can you see objects outside the room. Explain.
What are the different ways in which water gets contaminated ?
Mention against each of the following whether regular or diffused reflection will take place when a beam of light strikes. Justify your answer in each case.
(a) Polished wooden table (b) Chalk powder
(c) Cardboard surface (d) Marble floor with water spread over it
(e) Mirror (f) Piece of paper
Write 10 lines on the usefulness of microorganisms in our lives.
Differentiate between the following:
(a) Wildlife sanctuary and biosphere reserve
(b) Zoo and wildlife sanctuary
(c) Endangered and extinct species
(d) Flora and fauna
What is metamorphosis? Give examples.
Describe the ‘Green House Effect’ in your own words.
Give reasons for the following:
(a) Aluminium foils are used to wrap food items.
(b) Immersion rods heating liquids are made up of metallic substances.
(c) Copper cannot displace zinc from its salt solution.
(d) Sodium and potassium are stored in kerosene.
Why should paper be saved? Prepare a list of ways by which you can save paper.
Mark ‘T’ if the statement is true and ‘F’ if it is false.
(a) Generally non-metals react with acids. ( )
(b) Sodium is a very reactive metal. ( )
(c) Copper displaces zinc from zinc sulphate solution. ( )
(d) Coal can be drawn into wires. ( )
Paheli had heard that rainwater is as good as distilled water. So she collected some rainwater in a clean glass tumbler and tested it using a tester. To her surprise she found that the compass needle showed deflection. What could be the reasons?
A blacksmith hammers a hot piece of iron while making a tool. How does the force due to hammering affect the piece of iron?