Lakhmir Singh Manjit Kaur Class 6 Science 12th Chapter Electricity and Circuits Solution

Lakhmir Singh Manjit Kaur Solution Class 6 Science – Electricity and Circuits Solution All Exercise Short answer Type Questions, Very Short Type Questions, Long Answer Type Questions, MCQ Questions and Answer.

Electricity : A clean form of energy; Electricity runs many appliances and machines; Electricity is produced at power stations; Electricity can be dangerous; safe source of electricity : Electric Cell; Torch Bulb; Electric Circuits: Open Circuits and Closed Circuits; Electric Switch; How to make simple electric switch; Adding switch to the electric circuit; Torch; Electric etc.

Chapter 12 – Electricity and circuits

Very Short Answers Type Questions

(1) Ans: Electric cell

(2) Ans: Filament

(3) (a) Electric current can flow through metals. – True

(b) Instead of metal wires, a jute string can be used to make a circuit. – False

(c) Electric current can pass through a sheet of thermocol. –False

(d) The electricity produced by portable generators is safe to use in science experiments in the school laboratory. False

(4) Ans: Electric cells

(5) Ans: Torch bulb

(6) Ans: (a) Conductors: Those materials which allow electric current to pass through them are called conductors.

Example – Silver metals and copper metals.

(b) Insulators: Those materials which do not allow electric current to pass through them are called insulators.

Example – Wood and plastics.

(7) Ans: Switch

(8) Ans: Torch

(9) Ans: It is good conductors of electricity.

(10) (a) Which allow electricity to pass through them?

Ans: Conductor

(b) Which do not allow electricity to pass through them?

Ans: Insulator

(11) (a) Which is to be handled by us?

Ans: Insulator

(b) Through which electric current has to pass?

Ans: Conductor

(12) Ans: Copper is a good conductor of electricity.

(13) Ans:  For the purpose of good conductor.

(14) (i) Human body – poor conductor

(ii) Water – poor conductor

(15) Fill in the following blanks with suitable words:

(a) Air is not a conductor of electricity, it is an insulator.

(b) An electric cell has two terminals.

(c) A device which is used to ‘make’ or ‘break’ an electric circuit is called switch.

(d) Electricity flows in a/an closed circuit.

(e) The part of torch bulb that gives off light is the filaments.

Short Answer Type Questions

(16) Ans: Iron nail and key will make the bulb glow because they are conductors; Matchstick, eraser and glass bangle do not make the bulb glow because they are insulators.

(17) Ans: The switch is used to ‘open’ or ‘close’ a circuit.

• Some of the electrical appliances which have inbuilt switches are: table fan, room heater, room cooler, table lamp, torch etc.

(18) Ans: When we switch on an electrical appliance, we are closing its circuit by bridging the gap in it so that electric current can flow through the appliance and make it work.

(19) (a) cell – cell provides electricity

(b) bulb – Bulb converts electricity into light

(c) wires – Wires connect the cell, bulb and switch

(d) switch – Switch turns ‘on’ or ‘off’ electricity in the circuit.

(20) How would you connect a cell, torch bulb and switch so that the bulb lights up? Draw a sketch for this.

Ans: When the two terminals of a cell are connected to the two terminals of a bulb by using wires, the electric current passes through the filament of the bulb and it starts glowing.

(21) Ans: The switch is a simple device which is used to ‘open’ or ‘close’ a circuit.

• A switch works by opening and closing a gap in an electric circuit. When the switch is in the ‘off position’, a gap opens up in the circuit due to which electricity stops flowing in the circuit and hence the electrical stops working.

(22) Ans: Conductor – Steel, silver, copper, aluminium.

Insulators – Polythene, Rubber, air, wood, ceramics.

(23) Ans: Electricity cell is a source of safe electricity as well as portable electricity.

(24) Ans: Images

• When the torch light is not needed, the sliding switch is opened by pushing it backwards so that the circuit breaks and the bulb is turned off.

(25) Key, Eraser, Plastic scale, Matchstick, Glass bangle, Iron nail.

Ans: Use of conductors: Conductors allow electric current to pass through them.

Use of insulator: Insulator use for the outer covering of electric wires.

* Conductors – Key, Iron nail

* Insulator – Eraser, Plastic scale, Match stick, Glass bangle

(26) Ans: Because the metal screwdrivers having a wooden handle and wooden handle is insulator from the wooden handle current not pass hence the bulb would not glow.

(27) Ans: We wear rubber-soled shoes or rubber chappal while operating electrical appliances because rubber is an insulator which will protect us from electric shocks in case there is a leakage of electric current from the appliance.

(28) Ans: It is advisable to operate electric switches with dry hands because when we operate electric switches with wet hand then suddenly we get electric shock. Because the water is conductor it conduct current from the switch in our body. Hence it is advisable to operate electric switches with dry hands.

(29) Ans: Electricians wear rubber hand gloves while handling naked electric wirers because rubber is a good insulator and protects them from electric shocks.

(30) Ans:

(31) Ans: This is because if we join the terminals of a cell directly by a wire only, then the chemicals present in the cell get used up very fast, the cell gets damaged quickly and hence stops working.

(32) Ans: Torches, wristwatches, alarm clocks, transistor radios, TV remotes.

(33) Ans: (i) At the torch of a switch,

(ii) We can make an electric bulb glow and produce light.

(34) Ans: If electric wires and electrical appliances are handled carelessly, then

(i) Electricity can causes fires.

(ii) Person can get electric shock.

(35) Ans: A room heater, fans, electric kettle, washing machines and television set.

Long Answer Type Questions

(36) Ans: An electric circuit is apth along which electricity can flow.

Images

• (a) Completed circuit or closed circuit.
• (b) Open circuit.

(37) Ans: (a) The electric circuit in which there is no gap in the connections between the terminals of the cell wires and bulb is called a complete circuit.

(b) The electric circuit in which there is gap in the connections between the terminals of the cell wires and bulb etc is called an open circuit.

Images

(38) (i) in off position

(ii) in ‘on’ position.

(39) Ans:

• In a torch two cells are connected to a torch bulb through a sliding switch for on and off its light.

(40) Ans: When the bulbs gets fused the circuit breaks.

• Sometimes an electric bulb does not glow even if it is connected to a cell by wires without any gap in the circuit. This can happen if the bulb has got ‘fused’.

Multiplied Choice Questions (MCQs)

(41) Ans: (c) electric energy

(42) Ans: (b) electricity

(43) Ans: (d) battery

(44) (A) Sound        (B) Light       (C) Electricity     (D) Heat

Ans: (d) B and D

(45) Ans: (b) filament

(46) Ans: (a) closed

(47) Ans: (c) rubber glove

(48) Ans: (b) brass

(49) Ans: (a) graphite

(50) Ans: (c) heating effect of current

(51) (A) Electric clocks                          (B) Mobile phones
(C) Cameras                                     (D) T. V. remotes

Ans: (b) B and C

(52) Ans: (c) mica sheet

(53) Ans: (d) resistant to corrosion

(54) Ans: (d) it will get fused

(55) Ans: (c) tungsten.

Next Chapters Solution Link:

Chapter 1) Food: Where does it come from

 

Chapter 2) Components of Food Part-1

 

Components of Food Part-2