Class 6 Science - Chapter Changes Around Us NCERT Solutions | Give examples to explain the difference

A thick coating of a paste of Plaster of Paris (POP) is applied over the bandage on a fractured bone. It becomes hard on drying to keep the fractured bone immobilised. Can the change in POP be reversed?

A bag of cement lying in the open gets wet due to rain during the night. The next day the sun shines brightly. Do you think the changes, which have occurred in the cement, could be reversed?

A drawing sheet changes when you draw a picture on it. Can you reverse this change?

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

You accidentally dropped your favourite toy and broke it. This is a change you did not want. Can this change be reversed?

Some changes are listed in the following table. For each change, write in the blank column, whether the change can be reversed or not.

(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.

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?

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

List all items known to you that float on water. Check and see if they will float on an oil or kerosene.

How will you show that air is dissolved in water?

Which of the non-living things listed below, were once part of a living thing?

Butter, Leather, Soil, Wool, Electric bulb, Cooking oil, Salt, Apple, Rubber

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______________.

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?

The layer of air around the earth is known as ___________.

Name two foods each rich in:
(a) Fats
(b) Starch
(c) Dietary fibre
(d) Protein

Explain the process of making yarn from fibre.

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