Class 6 Science - Chapter Electricity and Circuits NCERT Solutions | Why should an electrician use rubber glo

Explain why the bulb would not glow in the arrangement shown in Fig. 12.13.

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

Using the "conduction tester" on an object it was found that the bulb begins to glow. Is that object a conductor or an insulator? Explain.

Would the bulb glow after completing the circuit shown in Fig. 12.14 if instead of safety pin we use an eraser?

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.

Complete the drawing shown in Fig 12.14 to indicate where the free ends of the two wires should be joined to make the bulb glow.

Fill in the blanks :
(a) A device that is used to break an electric circuit is called _______________.
(b) An electric cell has _______________ terminals.

The handles of the tools like screwdrivers and pliers used by electricians for repair work usually have plastic or rubber covers on them. Can you explain why?

What is the purpose of using an electric switch? Name some electrical gadgets that have switches built into them.

(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?

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

Select those objects from the following which shine:
Glass bowl, plastic toy, steel spoon, cotton shirt

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

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______________.

Give two examples of periodic motion.

A magnet was brought from different directions towards a toy boat that has been floating in water in a tub. Affect observed in each case is stated in Column I. Possible reasons for the observed affects are mentioned in Column II. Match the statements given in Column I with those in Column II.

Column I                                                                        Column II

Boat gets attracted towards the magnet                          Boat is fitted with a magnet with north pole towards its head

Boat is not affected by the magnet                                   Boat is fitted with a magnet with south pole towards its head

Boat moves towards the magnet if north                          Boat has a small magnet fixed along its length
pole of the magnet is brought near its
head

Boat moves away from the magnet                                  Boat is made of magnetic material                                                                                                             when north pole is brought near its head 

Boat floats without changing its direction                         Boat is made up non-magnetic material

Where are poles of a bar magnet located?

Fill in the blanks.
(a) ______________ is caused by deficiency of Vitamin D.
(b) Deficiency of ______________ causes a disease known as beri-beri.
(c) Deficiency of Vitamin C causes a disease known as ______________.
(d) Night blindness is caused due to deficiency of ____________ in our food.

Do you think it is better to use compost instead of chemical fertilisers? Why?