5. Write two insulators of electricity.
4. Write two conductors of electricity
VI. Short Answer Questions,
1. Write the principle on which a torch works.
2. What materials are needed to make an electric bulb glow?
3. Define closed and open electric circuits.
4. Describe construction and principle of an electric cell.
5. Describe construction and working of an electric bulb.
6. Discuss possible closed circuits in which bulb glows and also possible open
circuits in which bulb does not glow. Give your opinion based on facts.
VII
. Long Answer Questions.
1. (a) What is an electric circuit? Explain its kinds with suitable examples.
(b) What is an electric switch? Discuss how to make a simple electric switch
2. What are electric conductors and insulators? Explain with an experiment that
how
you can identify conductors and insulators from a given set of materials.
3. What do you mean by electric torch? Explain with an experiment that how
you can find out source of electricity in a torch.
Answers
re series and parallel circuits.
2ans=Answer:
m
Explanation:
5 ans=rubber and plastic
4 ans = metals and human being
Q6-1ans=When the switch of a flashlight is pushed into the ON position, it makes contact between two contact strips, which begin a flow of electricity, powered from the battery. The batteries are connected in such a way that electricity (flow of electrons) runs between the positive and negative electrodes of the battery.
2 ans = The bulb itself is made of glass and contains a mixture of gases, usually argon and nitrogen, which increase the life of the filament.
3ans =An open circuit is one where the continuity has been broken by an interruption in the path for current to flow. A closed circuit is one that is complete, with good continuity throughout. A device designed to open or close a circuit under controlled conditions is called a switch
4 ans = An electrical cell is an "electrical power supply". It converts stored chemical energy into electrical potential energy, allowing a current to flow from the positive terminal to the negative one via an external circuit. The positive terminal is called a cathode and the negative terminal is called an a node.
5ans=In an electric bulb there are two metal contacts at the base which connect to the ends of an electrical circuit. The metal contacts are attached to two stiff wires which are attached to a thin metal filament. ... The wires and the filament are housed in a glass bulb, which is filled with an inert gas, such as argon.
6ans =A few possibilities:
The contacts are not connected as well as they appear.
The wires have been tied or clamped to the terminals without stripping off the insulation.
Optical fibre was used instead of metallic wire.
The bulb is dead (burnt out).
The battery is dead.
There is no voltage source in the circuit.
A switch in series is open (switched off).
Something in series is blocking most or all of the current because, for example,
Q7-1ans=An electric circuit is a closed loop through which electric current can flow. A circuit must include a source of voltage and conductors such as wires to carry the current from the source of voltage and back again. Types of circuits a
2ans=Materials that allow electric current to flow through easily are called conductors. Most metals including aluminum are good conductors of electricity as well as water. Materials that do not allow electric current to flow well are insulators. Most items made of plastic and rubber are insulators.
3ans=person_pin CBSE library_books ELECTRICITY class CLASS 6 favorite 30.0 K
TABLE OF CONTENT
TABLE OF CONTENT
12.1 ELECTRIC CELL
12.2 A BULB CONNECTED TO AN ELECTRIC CELL
12.3 AN ELECTRIC CIRCUIT
12.4 ELECTRIC SWITCH
12.5 ELECTRIC CONDUCTORS AND INSULATORS
SUMMARY
KEY WORDS
EXERCISE
SOME SUGGESTED ACTIVITIES
We use electricity for many purposes to make our tasks easier. For example, we use electricity to operate pumps that lift water from wells or from ground level to the roof top tank. What are other purposes for which you use electricity? List some of them in your notebook.
Does your list include the use of electricity for lighting? Electricity makes it possible to light our homes, roads, offices, markets and factories even after sunset. This helps us to continue working at night. A power station provides us with electricity. However, the supply of electricity may fail or it may not be available at some places. In such situations, a torch is sometimes used for providing light. A torch has a bulb that lights up when it is switched on. Where does the torch get electricity from?