Class 6 Science - Chapter Motion and Measurement of Distances NCERT Solutions | Why could you not use an elastic measuri

Why can a pace or a footstep not be used as a standard unit of length?

Write the similarities and differences between the motion of a bicycle and a ceiling fan that has been switched on.

The distance between Radha's home and her school is 3250 m. Express this distance into km.

Fill in the blanks:
(i) One metre is ______________ cm.
(ii) Five kilometre is ______________ m.
(iii)Motion of a child on a swing is ______________.
(iv)Motion of the needle of a sewing machine is ______________.
(v) Motion of wheel of a bicycle is______________.

While measuring the length of a knitting needle, the reading of the scale at one end is 3.0 cm and at the other end is 33.1 cm. What is the length of the needle?

Arrange the following lengths in their increasing magnitude:
1 metre, 1 centimetre, 1 kilometre,1 millimetre.

The height of a person is 1.65 m. Express it into cm and mm.

Give two examples of periodic motion.

Give two examples each, of modes of transport used on land, water and air.

(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.

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

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.

Answer the following:
(a) What is a ball and socket joint?
(b) Which of the skull bones are movable?
(c) Why can our elbow not move backwards?

Why should an electrician use rubber gloves while repairing an electric switch at your home? Explain.

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.

Fill in the blanks:
a) Plant fibres are obtained from_________ and ________ .
b) Animals fibres are __________ and ___________ .

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?

In a completely dark room, if you hold up a mirror in front of you, will you see a reflection of yourself in the mirror?

How will you separate sand and water from their mixture?

Lemonade is prepared by mixing lemon juice and sugar in water. You wish to add ice to cool it. Should you add ice to the lemonade before or after dissolving
sugar? In which case would it be possible to dissolve more sugar?

Match the objects given below with the materials from which they could be made. Remember, an object could be made from more than one material and a
given material could be used for making many objects.

Objects                Materials
Book                     Glass
Tumbler                Wood
Chair                     Paper
Toy                        Leather
Shoes                   Plastics

How would you obtain clear water from a sample of muddy water?