Solutions for Class 6 Science

Chapter 12 Electricity and Circuits

1. Fill in the blanks:
(a) A device that is used to break an electric circuit is called_______________
(b) An electric cell has___________
Ans:
(a) switch
(b) two

2. Mark ‘True’ or ‘False’ for the 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 thermocol.
Ans:
(a) True
(b) False
(c) False.

3.Explain why the bulb would not glow in the arrangement shown in
fig

Ans: The bulb would not glow in the arrangement shown in figure because
the one end of tester/screw driver is made up of plastic which does not allow
the electric current to flow through it.

4. Complete the drawing shown in Fig. 12.9 to indicate where the

free ends of the two wires should be joined to make the bulb glow.
Ans:

5. What is the purpose of using an electric switch? Name some

electrical gadgets that have switches built into them.
Ans: Electric switch is used to make electric circuit open or closed for a
particular appliance and hence with the help of a switch we can use an
appliance according

6. Would the bulb glow after completing the circuit shown in Fig.
12.9 if instead of safety pin we use an eraser?
Ans: No, since eraser is an insulator so it does not allow the current to pass.
Hence the bulb will not glow.
7. Would the bulb glow in the circuit shown in Fig. 12.11.

Ans: Yes, the electric circuit is closed so the bulb will glow.

8. 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.
Ans: Yes, if the object is good conductor of electricity then current will pass
through conduction tester and the bulb will glow. Hence the object will be a
conductor of electricity.

9. Why should an electrician use rubber gloves while repairing an

electric switch at your home? Explain.
Ans: Our body is good conductor of electricity and rubber is insulator. During
repairing work if the body comes in contact with current carrying wire then
there will not be any accident as rubber does not allow the passage of
current through it. Hence electrician uses rubber gloves while repairing an
electric switch.

10. 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?
Ans: Plastic or rubber is an insulator which does not allow electric current to
pass through it. The handles of the tools like screwdrivers and pliers used by
electricians for repair have covering of plastic or rubber so that electric
current may not pass through these tools to the body of the electrician to
harm him.

Class 6 Science Chapter 12 VERY SHORT ANSWER TYPE QUESTIONS

1. What is the direction of flow of current in a dry cell?

Ans: . The current flows in closed circuit from +ve to -ve terminal of cell.
2. Name the +ve terminal of dry cell.
Ans:. Carbon rod with a metal cap on it.

3. Name the -ve terminal of a dry cell.

Ans: Zinc metal plate.

4. What is dry cell?

Ans: It is a device which converts chemical energy into electrical energy.

5. What is solar cell?

Ans: A device which converts solar energy into electrical energy.

6. What is open circuit?

Ans: An electric circuit in which electrical contact at any point is broken is
called open circuit.

7. Write one use of insulators.

Ans: Insulators are used in making switchboard, handles of testers, screw
drivers.

8. What is the name of thin wire in the electric bulb?

Ans: Filament.

Class 6 Science Chapter 12 SHORT ANSWER TYPE QUESTIONS

1. Mention two advantages of a dry cell.

Ans:
1. It converts chemical energy into electrical energy.
2. It is light and small in size.
2. Draw a diagram showing the two terminals of a bulb.
Ans:

3. Draw the circuit diagram for operating a bulb with the help of a
dry cell.
Ans:

4. Define conductors and insulators. Give one example of each.

Ans: A conductor is that which easily allows the passage of current through
it. Example: Aluminium or any metal.
An insulator is that which does not allow the passage of current through it.
Example: Rubber.

5. Identify conductors and insulators from the following:Eraser,

paper, matchstick, copper wire, pencil lead, polythene
Ans: Conductors: Copper wire, pencil lead.
Insulator. Eraser, paper, matchstick, polythene.

6. Name the scientist who invented electric cell and the scientist
who invented electric bulb.
Ans: Electric cell: Alessandro Volta.
Electric bulb: Thomas Alva Edison.

7. Give one activity to prove that air is an insulator.

Ans: Take an electric circuit, keep the terminals unconnected in the air. The
bulb do not glow, as air is an insulator and does not allow the current to flow
through it.

8. In any electric circuit, when the switch is on and the current flows
through it why do the wire, switches, bulb or devices become hot?
Ans.: This is because electric energy changes into heat energy.

9.The headlights of a car have reflectors behind the bulb. What is

the function of reflectors?
Ans: The reflector helps in reflecting the light into a focussed area.

10.If you touch an electric wire carrying current you get a shock, but
if on the same wire the birds sit they do not get any shock/current.
Explain why?
Ans: When we hold the wire carrying current then the circuit is closed and
the current flows from our body and enters earth but the birds sitting on the
same wire do not get any current as the circuit is not complete. If the bird
touches the earth wire, it will also die due to electric shock.

Class 6 Science Chapter 12 LONG ANSWER TYPE QUESTIONS

1.(1)What is electric circuit?

(2)How many types of electric circuit are there? Define them.
(3)Draw a diagram to show the closed circuit for switch, bulb and
dry cell.
Ans:
(1)The diagram that shows the path of electric current is called electric
circuit.
(2)There are two types of electric circuit:
(a) Open electric circuit
(b) Closed electric circuit
(a)Open electric circuit: The circuit in which electrical contact at any point
is broken is called open electric circuit.
(b)Closed electric circuit: The circuit in which electric current flows from
one terminal of a cell or battery to the other is called a closed circuit.

In

Electricity and Circuits Class 6 Extra Questions Very Short Answer Type

Question 1.

Name a good conductor of electricity which is not a metal.

Answer:

Air

Question 2.

Name the material that glows inside the bulb.

Answer:

Filament

Question 3.

What kind of cells are used in TV remotes?

Answer:

Pencil cells

Question 5.

What is a cell?

Answer:

It is a device that produces electricity.

Question 6.

What is electricity?

Answer:

The flow of an electric current constitutes electricity.

Question 7.

How many terminals are there in a cell?

Answer:

There are two terminals in a cell.

Question 8.

What is the main function of a switch?

Answer:

It is used to regulate the flow of current in a circuit.

Question 9.

Name some metals which are conductors.

Answer:

Silver, copper, aluminium, etc.

Question 10.

Name some conductors which are not metals.

Answer:

Moist air, salt solution, impure water, graphite, etc.

Question 11.

Name some insulators of electricity.

Answer:

Mica, ebonite, glass, wood, dry air, etc.

Question 12.

Which type of material is used in electric appliance as protective measures?

Answer:

Insulator

Question 13.

What is an open circuit?

Answer:

When there is a gap between two terminal, the circuit is called an open circuit.
Question 14.

Can rubber or jute be used instead of metal wire to connect circuit?

Answer:

No, we cannot use rubber or jute to connect circuit wires.

Question 15.

How is electricity produced by an electric cell?

Answer:

An electric cell produces electricity from chemicals stored in it.

Question 16.

Name two metal used to connect wires.

Answer:

Copper and aluminium.

Question 17.

When does a bulb glow?

Answer:

A bulb glows only when the circuit is complete.

Question 18.

Why is tungsten used as a filament?

Answer:

Tungsten has high melting point and high resistance, hence it is used as filament.

Question 19.
Why are electric wire, covered with rubber and plastic?

Answer:

To prevent electric shocks as they are insulators.

Question 20.

In which of the following circuits A, B and C given below, the cell will be used up very rapidly?

Electricity and Circuits Class 6 Extra Questions and Answers Science Chapter 12 1

Answer:

In circuit C the cell will be used up very rapidly because two bulbs are connected to a single cell.

Electricity and Circuits Class 6 Extra Questions Short Answer Type

Question 1.

Why we are advised not to touch electric appliances and switches with wet hands?

Answer:

Water is a good conductor of electricity and if our hands are wet it can pass to us quickly giving us an
electric shock.

Question 2.

Define an electric cell and a battery.

Answer:

A cell is an electric device that produces electricity. When two or more cells are joined together, it is
called a battery.

Question 3.

Define a conductor.
Answer:

The substance which allows an electric current to pass through it, is called a conductor, e.g., metals like
gold, silver, etc.

Question 4.

What is an insulator?

Answer:

The substance which does not allow current to pass through it, is called an insulator, e.g., eraser, paper,
polythene, etc.

Question 5.

What do you mean by an electric circuit?

Answer:

The closed path along which the electric current flows from one terminal to another is called as an
electric circuit.

Question 6.

What is an open circuit? Does current flow in it?

Answer:

The circuit in which arrangements of components is disturbed any way or electric contact of any point is
broken is called an open circuit. An electric current does not flow in an open circuit as the electrical path
required for flow of current is not completed.

Question 7.

Why is a copper wire usually covered with rubber or plastic?

Answer:

Rubber or plastics are insulators. They prevent short circuiting and electric shocks if by mistake any living
things come in contact with the wires.
Question 8.

Is air a conductor or an insulator? Explain.

Answer:

If air is dry then it is an insulator or bad conductor of electricity as it doesn’t conduct electricity when the
circuit is open. If air is moist then it acts as conductor.

Question 9.

Why does a cell stop producing electricity after sometime?

Answer:

After sometime, all the chemicals in an electric cell is used up. Thus, no chemical reaction takes place to
produce electrical energy.

Electricity and Circuits Class 6 Extra Questions Long Answer Type

Question 1.

What is bulb? Mention two main conditions necessary to make the bulb glow.

Answer:

Electricity and Circuits Class 6 Extra Questions and Answers Science Chapter 12 2

A bulb is an electric device which gives us light when a suitable material inside it called filament gets
heated up to a high temperature. It runs on electricity viz., when an electric current passes through it, it
glows.

Two main conditions necessary to make the bulb light up are:

(i) Connect the positive (+ve) terminal of the left cell with the negative (-ve) one of the right
side cell using a wire.
(ii) Close the switch to complete the circuit.

Question 2.

Explain how does an electric current flow in an electric circuit.

Answer:
An electric current flows from the positive (+ve) terminal to the negative (-ve) terminal of the cell in the
circuit through the connecting wires as shown in the given figure.

Electricity and Circuits Class 6 Extra Questions and Answers Science Chapter 12 3

The current flows only when the circuit is complete, i.e., all the connections are intact and the key is
switched ‘on’. We see that the bulb glows. But when the wires are broken or not properly connected to
the terminals of the cell, the circuit is incomplete and the current does not flow in the circuit. The bulb
does not light up.

Question 3.

What is torch? Give its various parts and explain its working. Also give its labelled diagram.

Answer:

A torch is an electric device that runs on electricity. It is actually a compact electric circuit. Its various
parts are-a metallic or plastic casing, bulb, reflector, slide, switch, metal switch contact.

An electric current flows in a closed circuit only. In a torch, the cells are connected to a small bulb
through a slide switch. When this slide switch is slided forward cell contact is complete with the bulb.
The electric circuit is closed or complete.

The electric current starts flowing from the terminal of the cell and returns to the other terminal. Thus,
the bulb starts glowing and gives light. On the other hand, on switching off, the contact between the
metal strips is broken and the current stops flowing. Thus, the bulb stops glowing.

Electricity and Circuits Class 6 Extra Questions and Answers Science Chapter 12 4

Question 4.

What is a circuit? Name its different components and draw a labelled diagram of a circuit.

Answer:

Electricity and Circuits Class 6 Extra Questions and Answers Science Chapter 12 5

A circuit is a path along which an electric current flows. It is made up of various electrical components
which are discussed below:

There is a cell or a battery in the circuit that is used as a source of electric current.

There is an electric switch that is used to regulate the flow of current. It is also called ‘key’. When the
switch is ‘on’, the current flows in the circuit and when it is ‘off, the current does not flow.
A bulb is connected to the circuit to confirm the flow of current. When it lights up, the circuit is said to
be complete, i.e., current is flowing.

On the other hand, when the bulb does not glow, the circuit is said to be incomplete, i.e., current is not
flowing.

The most important component of the circuit is the connecting wire which connect all the components
of the circuit to make the current flow.

Question 5.

Describe a closed and open circuit with the help of diagrams.

Answer:

Electricity and Circuits Class 6 Extra Questions and Answers Science Chapter 12 6

A circuit which is complete in all respect, i.e., its all connections are intact is called a closed circuit. When
the switch is on, the current flows in it and the bulb glows (Fig. 12.22a). On the other hand, a circuit is
called open or not complete (Fig. 12.22b), when connections are not intact, i.e., broken. In an open
circuit, when the switch is on, the bulb does not glow. It means that current is not flowing in the circuit.
This is due to broken wires or all components in the circuit are not connected properly.

Question 6.

Mention different safety measures and precautions while using electricity and electrical appliances.

Answer:

Electricity is very useful to us. It has made our life comfortable, easy and luxurious. On the other hand, it
is dangerous also. It may cause great mishappenings, injuries and sometimes even death. So we must
adopt some safety measures and take precautions discussed below:

Never touch electrical switches or gadgets when your body is wet.

If you need to operate or repair any electrical appliances, wear rubber hand gloves and stand on a dry
wooden or plastic base.

Never play with electric sockets or wires.

In case of short circuit or a spark in a switch, put the main switch off immediately with the help of a
plastic or wooden stick.

In case of fire in electric wires, never use water to extinguish it. First switch off the mains, then use dry
sand to extinguish the fire.

Electricity and Circuits Class 6 Extra Questions HOTS

Question 1.
Two bulbs are connected to a cell as shown in Fig. 12.23. Bulb A got fused. Will the bulb B glow in this
circuit? Why?

Answer:

Electricity and Circuits Class 6 Extra Questions and Answers Science Chapter 12 7

No, the bulb B will not glow because there is only one path from the source of current. If any one of the
light bulbs get fused, the entire circuit will stop operating.

Question 2.

You have a single piece of connecting wire. Can you make a bulb glow without cutting the wire into two?
Explain with the help of a circuit diagram.

Answer:

Yes, we can glow the bulb by joining one end of the wire to the negative terminal of battery and other to
the metal cap of the bulb. Then by placing the bulb on the positive terminal of the cell will make the
bulb glow.

Electricity and Circuits Class 6 Extra Questions and Answers Science Chapter 12 8

Question 3.

Which of the labels 1, 2, 3, 4 or 5, shows the terminals of the bulb?

Electricity and Circuits Class 6 Extra Questions and Answers Science Chapter 12 9

Answer:

Label 3 and 4 shows the terminals of the bulb.

Question 4.

Two different ways are shown below to connect a bulb with a cell.

Electricity and Circuits Class 6 Extra Questions and Answers Science Chapter 12 10

(i) What will be the direction of the current through the bulb in both the cases. (Q to P or P to
Q)
(ii) In which case the bulb will glow?
(iii) Does the brightness of the glowing bulb depend on the direction of current through it?

Answer:

(i) In Fig. A, current will flow from Q to P and in Fig. B current will flow from P to Q.
(ii) In both of the cases bulb will glow as the circuit is complete.
 (iii) No.

Electricity and Circuits Class 6 Extra Questions Value-Based (VBQs)

Question 1.

When Sheena’s classmates leave for games, library, yoga, etc., classes, Sheena always remembers to
switch off the lights and fans of her class. For this practice she was honoured by the president of eco-
club.

(a) What is electricity?

(b) What are the sources of electricity in your home?

© What values of Sheena is shown here?

Answer:

(a) Electricity is a form of energy used to power machines and electrical appliances.

(b) We get electricity in our home through cell, power house and solar cells.

© Sheena is an eco-friendly, responsible and intelligent girl.

Question 2.

After taking a bath Rahman went to his room. As soon as he raised his hand to switch on the light, his
mother shouted out loudly. He was very astonished, with the strange behaviour of his mother. His
mother came to him and explained him the reason “why he shouldn’t be touching the electrical items
with wet hands”. Rahman made up his mind to spread this awareness in the school. So he decided to
give a small speech on this topic during the school assembly.

(a) What are electrical appliances?

(b) What would have happened if Rahman touched the switch with his wet hand?

© What value of Rahman is shown here?

Answer:

(a) Devices that run on electricity are called electrical appliances.

(b) He might have got shock.

© Rahman is a responsible, sensible, caring and confident boy.