Class 6 Science - Chapter Light, Shadows and Reflections NCERT Solutions | In a completely dark room, if you hold u

Can you think of creating a shape that would give a circular shadow if held in one way and a rectangular shadow if held in another way?

Classify the objects or materials given below as opaque, transparent or translucent and luminous or non-luminous:

Air, water, a piece of rock, a sheet of aluminium, a mirror, a wooden board, a sheet of polythene, a CD, smoke, a sheet of plane glass, fog, a piece of red hot
iron, an umbrella, a lighted fluorescent tube, a wall, a sheet of carbon paper, the flame of a gas burner, a sheet of cardboard, a lighted torch, a sheet of cellophane, a wire mesh, kerosene stove, sun, firefly, moon.

Rearrange the boxes given below to make a sentence that helps us understand opaque objects.

(a) Which kind of garbage is not converted into compost by the redworms?
(b) Have you seen any other organism besides redworms, in your pit? If yes, try to find out their names. Draw pictures of these.

To walk through a waterlogged area, you usually shorten the length of your dress by folding it. Can this change be reversed?

Do you find that all living beings need the same kind of food?

Name the major nutrients in our food.

Classify the following fibres as natural or synthetic:
nylon, wool, cotton, silk, polyester, jute

Name five objects which can be made from wood.

Why do we need to separate different components of a mixture? Give two examples.

Correct the following statements and rewrite them in your notebook.
(a) Stem absorbs water and minerals from the soil.
(b) Leaves hold the plant upright.
(c) Roots conduct water to the leaves.
(d) The number of petals and sepals in a flower is always equal.
(e) If the sepals of a flower are joined together, its petals are also joined together.
(f) If the petals of a flower are joined together, then the pistil is joined to the petal.

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.
(d) The contraction of the _____________ pulls the bones during movement.

What is a habitat?

Why could you not use an elastic measuring tape to measure distance? What would be some of the problems you would meet in telling someone about a distance you measured with an elastic tape?

If a plant has leaves with reticulate venation, what kind of roots will it have?

Name the part of the plant which produces its food. Name this process.

How will you prove that air supports burning?

Draw (a) a leaf, (b) a taproot and (c) a flower, you have studied for Table 7.3.

Discuss :
(a) Is garbage disposal the responsibility only of the government?
(b) Is it possible to reduce the problems relating to disposal of garbage?

From which parts of the plant cotton and jute are obtained?

Would the bulb glow in the circuit shown in Fig. 12.15?

How are clouds formed?

Do you find that all living beings need the same kind of food?