Class 6 Science - Chapter Changes Around Us NCERT Solutions | Some changes are listed in the following

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?

Give examples to explain the difference between changes that can or cannot be reversed.

(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?

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

Match the items in Column I with one or more items of Column II.

Column I                           Column II
Upper jaw                          have fins on the body
Fish                                    has an outer skeleton
Ribs                                   can fly in the air
Snail                                  is an immovable joint
Cockroach                         protect the heart
                                          shows very slow movement
                                          have a streamlined body

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

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

How do plants and animals help each other in the exchange of gases in the atmosphere?

Suppose you want to dry your school uniform quickly. Would spreading it near an anghiti or heater help? If yes, how?

Mark 'True' or 'False' for following statements:
(a) Electric current can flow through metals.
(b) Instead of metal wires, a jute string can be used to make a circuit.
(c) Electric current can pass through a sheet of thermo Col.

Column I shows different positions in which one pole of a magnet is placed near that of the other. Column II indicates the resulting action between them for each situation. Fill in the blanks.

Column I                           Column II
N - N                                   _________
N - _________                    Attraction
S - N                                   _________
_________ - S                    Repulstion

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?

State for each of the following whether it is due to evaporation or condensation:
(a) Water drops appear on the outer surface of a glass containing cold water.
(b) Steam rising from wet clothes while they are ironed.
(c) Fog appearing on a cold winter morning.
(d) Blackboard dries up after wiping it.
(e) Steam rising from a hot girdle when water is sprinkled on it.