Electricity Circuits and Their Components Class 7 Extra Questions and Answers Science Chapter 3

By tackling these Class 7 Science Extra Questions and Class 7 Curiosity Chapter 3 Extra Question Answer Exploring Substances Acidic Basic and Neutral, students will build a solid foundation in the topic.

Class 7 Science Chapter 3 Electricity Circuits and Their Components Extra Questions

Class 7 Science Chapter 3 Extra Questions on Electricity Circuits and Their Components

Electricity Circuits and Their Components Class 7 Very Short Question Answer

Question 1.
What is used to generate electricity in hydroelectric power houses?
Answer:
Force of falling water.

Question 2.
What is switch?
Answer:
Switch is simple device to complete or break the circuit.

Question 3.
When the electric circuit is called closed?
Answer:
When electric current flows in it.

Question 4.
What is the full form of L.E.D.?
Answer:
Full form of L E D. : L-light, E-emitting, D-diode (light emitting diode).

Question 5.
What is direction of current?
Answer:
From positive end to negative end.

Question 6.
How do we use electricity in communication?
Answer:
In mobile phones and internets.

Question 7.
Through what electricity is flown in circuit?
Answer:
Through conductor

Question 8.
How the circuits are represented?
Answer:
Circuits are represented by symbols.

Question 9.
How the bulb glows?
Answer:
Filament get hot and glow.

Question 10.
Write two conversion of electric energy?
Answer:
Light and heat

Question 11.
What is the importance of switch in an electric circuit?
Answer:
Switch allowed us to turn ON and OFF to an electric device.

Question 12.
Give examples of two insulators.
Answer:
Rubber and plastic

Question 13.
Give examples of two conductors.
Answer:
Copper and iron

Question 14.
Through which materials current cannot pass?
Answer:
Wooden, plastics

Question 15.
What is the main reason behind bulb do not glow?
Answer:
An opened circuit.

Electricity Circuits and Their Components Class 7 Short Question Answer

Question 1.
Define an electric circuit.
Answer:
Electric circuit is a way in which cell, conducting wire, switch and bulb are connected. Closing circuit allows the flow of current and bulb glows.

Question 2.
Write differences in conductor and insulator.
Answer:
Conductors are the material, through which current flows like copper. Insulators are the material through which current does not flow like rubber. Conductors are useful, insulators provides us safely .

Question 3.
Explain importance of symbols in making circuit diagram.
Answer:
Using symbols in circuit diagram makes the diagram easy, clear and similar on every place. It saves time and makes easy to understand the circuit.

Question 4.
How do a bulb works?
Answer:
Heat is generated in filament of bulb when current flow s. Filament gets hot and glow and emit light.

Question 5.
What do you understand by a fused lamp? Answer: When a lamp does not glow even after connecting to a cell. It is called fused lamp because the filament of lamp is broken and it does not allow the flow of current and preventing the lamp to glow.

Question 6.
How do you identify a cell’s positive and negative side with closed eyes?
Answer:
In a cell there are two sides, one has a small protruding metal cap which is positive side and a flat metal disc on another side which is negative side. So by touching the protruding metal cap it can be identified.

Question 7.
Give a brief detail on importance of electric energy.
Answer:
Electric energy produced with the flow of electric charges through electric current. It is used in lights, fans, computers, motors, refrigerators and many other appliances. It is the most essential energy of modem lifestyle.

Question 8.
Identify conductors among the following: Metal spoons, coins, rubber, glass, keys, pins, plastic scale, wooden block, sewing needle, pencil lead, paper.
Answer:
Conductors among the above things are: Metal spoons, coins, keys, pins, sewing needle and pencil lead.

Electricity Circuits and Their Components Class 7 Long Question Answer

Question 1.
Explain electric circuit by making diagram.
Answer:
In a normal circuit cell, switch and bulb are comiected with wires. When switch is turned on, circuit get closed and lamp/bulb glow and when switch is turned off, circuit opened and bulb will turn off.

Question 2.
Write importance of Conductors and Insulators.
Answer:
Conductors flow electric current through them like copper, iron etc. Which is essential in electric devices. And insulators stop the flow of electric current like rubbers, plastics and save us from electric shocks. Both are equally useful in houses and industry.

Question 3.
What are the main components of an electric circuit?
Answer:
Main components are
(i) Cell/Battery – Source of electric energy
(ii) Wire – For flow of current
(iii) Switch – To open and close the electric circuit
(iv) Bulb/Device – To convert electric energy into light/work.

Question 4.
Write applications of electric energy.
Answer:
Electric energy used in fans, bulbs, television, refrigerator.etc. in houses and to run machines in industries, for irrigation in agriculture and also in transport and communications. It is a foundation stone in modem life.

Question 5.
Describe working principle of a bulb.
Answer:
There is a filament in bulb made up of tungsten. When electric current flows then it get hot and emit light and heat. The outer glass bulb covering prevents it with air. Bulb converts electric energy into light.

Question 6.
What is the difference between conductors and insulators? Give example of use in daily – life.
Answer:
The materials through which electric current flows easily are called conductors. Ex. : Iron, Aluminium, Copper etc. They are used to flow electric current in wires, sockets and electric devices. And oppositely, the materials through which electric current cannot flow are called insulators. Ex. : Rubber, plastic, wood and glass. These are helpful to save us from electric shocks: That is why the wires are covered with plastic and handles of electric appliances are made with mbber or wood. Thus, a balanced use of conductors and insulators ensures our comfort and safety both.

Question 7.
If the power supply in your area disrupted for two days. What will be the impact on life?
Answer:
Life will affected extremely if there is no electricity for two days. Fans, refrigerator, lights would not run and mobile phones would not charged. Food may be spoilt and communication will be disrupted. Students would not be able to study online and night study will be disturbed. The machines in hospitals will stop working and life of patients will be in danger. There will be economic loss due to disturbance in working in industry and factories. Transport and traffic signal will be disturbed. It is clear that absence of electricity our daily life will be chaotic and the importance will be understood more deeply.

Question 8.
How L.E.D. bulbs are different from incandescent bulbs?
Answer:
The filament get hot and glows to produce light in incandescent bulbs whereas there is no filament in L.E.D. (light emitting diode) even a semi-conductor emits light. Electric current flows in a single direction in L.E.D. It is more capable in reference of energy because it consume less electricity and runs for long time. Incandescent bulb produces more heat and spoilt soon. L.E.D.s are cool and better for environment. Nowadays use of L.E.D. in houses, offices, and roads is increasing.

Question 9.
What is an electric circuit? Explain its ‘ON’, ‘OFF’ position with example.
Answer:
Electric circuit is a closed way, through which electricity flows. Cell, battery, wire, switch and bulb are its main components. When all components are connected properly and switch is in ‘ON’ position then from positive terminal to negative electric current flow and the bulb glows. It is called a closed circuit. Oppositely, if switch is in ‘OFF’ position or any wire is broken in way of current then bulb will not glow’ and called as open circuit. In easy words, it can be said that circuit only works when it is complete and connected.