While lighting a candle, Paheli observed the following changes:
(i) wax was melting, (ii) candle was burning. (iii) size of the candle was reducing. (iv) melted wax was getting solidified.
Of the above, the changes that can be reversed are:
A)
(i) and (ii)
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B)
(ii) and (iii)
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C)
(iii) and (iv)
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D)
(i) and (iv)
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The process of returning back of light ray from a shining surface is called
A)
reflection
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B)
refraction
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C)
inversion
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D)
lateral inversion
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...................... is an electric device which can easily close or open an electric circuit.
A)
Filament
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B)
Electric bulb
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C)
Electric switch
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D)
Electric cell
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North pole of a magnet can be identified by:
A)
another magnet having its poles marked as north pole and south pole
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B)
another magnet no matter whether the poles are marked or not
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C)
using an iron bar
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D)
using iron fillings
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The quantity of water required to produce one page of your book is:
A)
one bucket
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B)
ten buckets
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C)
two glasses
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D)
few drops
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Which statement out of the following is incorrect?
A)
Use of Charkha was popularized by Mahatma Gandhi as a part of the Independence Movement.
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B)
In India, jute is mainly grown in Kerala and Punjab.
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C)
To make fabric, the fibers are first converted into yarns.
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D)
Sufi saint Kabir was a weaver.
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Boojho found a bag containing the following materials
(i) Mirror (ii) Paper stained with oil (iii) Magnet (iv) Glass spectacles
Help Boojho in finding out the material(s) which is/are opaque:
A)
(i) only
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B)
(iv) only
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C)
(i) and (iii)
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D)
(ii) and (iv)
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Which amongst the following methods would be most appropriate to separate grains from bundles of stalks?
A)
Hand picking
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B)
Winnowing
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C)
Sieving
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D)
Threshing
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An iron ring is heated. Which of the following statements about it - incorrect?
A)
The ring expands.
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B)
The ring almost comes to the same size on cooling.
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C)
The change in this case is reversed.
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D)
The ring changes its shape and the change cannot be reversed.
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Read the following sentences about photosynthesis:
(i) Sunlight, carbon dioxide, chlorophyll and water are necessary. (ii) Oxygen is absorbed. (iii) Leaves carry out photosynthesis. (iv) Proteins are made during photosynthesis.
Choose the correct pair of sentences that are true to photosynthesis:
A)
(iii) and (iv)
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B)
(i) and (iii)
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C)
(ii) and (iv)
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D)
(i) and (iv)
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Answer the following questions in one word or in a sentence only. (i) Write one example for each of the following type of motion: (a) Rectilinear motion (b) Periodic motion
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Answer the following questions in one word or in a sentence only. (ii) Can we form shadow with the help of light and an opaque object only?
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Answer the following questions in one word or in a sentence only. (iii) A tailor was stitching buttons on his shirt. The needle got slipped from his hand onto the floor. How can you help the tailor to find the needle?
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Answer the following questions in one word or in a sentence only. (iv) Define condensation.
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Answer the following questions in one word or in a sentence only. (v) What type of garbage is used for composting?
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Answer the following questions in one word or in a sentence only. (vi) What type of objects a chair and a shoe are?
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(i) What type of adaptation is found in a deer that helps it to see in all the directions? (ii) How does exchange of gases take place in an earthworm?
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Why should an electrician use rubber gloves while repairing an electric switch?
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Give the properties of a magnet.
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Why do wet clothes dry up quickly in sunlight compared to shades?
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Explain why air is considered a mixture?
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Among notebooks, newspaper, plastic coated papers. Find out, which of these can be recycled?
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Recently, a ban on plastic bags has been imposed in many places. Is the ban justified? Give reasons in three sentences.
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Beera, a farmer would clear his field every day, and burn dry leaves fallen on the ground. After some time he found that those living in huts near his field were suffering from cough and breathing problems. (i) Can you explain why? (ii) Also suggest an environment friendly way to dispose the dry leaves.
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Observe the picture given in Fig. carefully and answer the following questions. (a) What is covering the nose and mouth of the policeman? (b) Why is he putting a cover on his nose? (c) Can you comment on air quality of the place shown in the Fig.?
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Why should we eat a balanced diet? Name the vitamin that gets destroyed on heating.
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Name two hand operated devices that are used for spinning. Name the person who made the charkha popular.
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Write three advantages of grouping of materials.
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Give examples of three quick natural changes.
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Will a leaf taken from a potted plant kept in a dark room for a few days turn blue black when tested for starch? Give reasons for your answer.
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Fill in the blanks: (a) Joints of the bones help in the ................ of the body. (b) A combination of bones and cartilages forms the ............. of the body. (c) The bones at the elbow are joined by a ................ joint.
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(i) Why is reproduction important for organisms? (ii) What are the specific features present in a deer that help it to detect the presence of predators like lion?
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Boojho was riding in his bicycle along a straight road. He classified the motions of various parts of the bicycle as (i) rectilinear motion, (ii) circular motion and (iii) both rectilinear as well as circular motion. Can you list one part of the bicycle for each type of motion? Support your answer with reasons.
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Give examples to explain the difference between changes that can or cannot be reversed.
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Write the similarities and differences between the motion of a bicycle and a ceiling fan that has been switched on.
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Complete the drawing shown in the Fig. to indicate where the free ends of the two wires should be joined to make the bulb glow.
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Explain the process of rooftop rain water harvesting with the help of a suitable diagram.
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