A) transistors

A rectifier is sometimes called a.... в) diode

A relay consists of an electro-magnet which, when energized, attracts a soft... armature. д) iron

A remote control may be brought about by the use of a.... г) relay

A simple b,.ltery convt-its chemical energy into... energy. г) electrical

A simple diode consists of a... that has only two electrodes: anode and cathode. г) valve;

A simple thermionic valve is called a..- because it has two electrodes. 6)diode

A station that uses the power of falling water is known as a... station. д) hydroelectric

A step-down... reduces the input voltage. д) transformer

A switch is used in almost every piece of electrical.... д) apparatus

A tetrode lias four. an a pentode five.... д ) electrodes

A transistor is a.... г) semiconductor

A transistor lias three electrodes, a base. an.... and a collector. д) emitter

A transistorized circuit is simpler, smaller, and... stronger. 6) technically

A transformer is a static..., it has no moving parts. a) machine

A unit of resistance is called an.. a) ohm

A unit of power is.... д) watt

A unit of power is.... д) watt

A valve is a... that allows a flow in one direction only. д) device

Alternating... is the kind of electricity that is generated in power stations for domestic and industrial use, the direction of flow

changes very quickly. г) current

Amber is a fossil resin.... in colour а) yellowish

An electric current is the... of electrons. б) How

Any material that will not permit the flow of electricity is known as an.... г) insulator

Any material that will allow electricity to flow through it is called a.... 6) conductor

A... changes alternating cui-rent to direct current. 6) rectifier

A...consists of two coits of wire that are wound around a soft iron core. 6) iranslbrmer

A... is a valve with three electrodes, an anode, a cathode and a control grid. г) triode

A... is used to increase or decrease the voltage of an electric power supply. д) transformer

Common... materials include air, oil. glass, porcelain, mica, rubber and plastics. a)insulating

Current, voltage and resistance bear a definite... to one another. г) relationship

…can be very dangerous if it is carelessly used. в) electricity

…current is the kind of electricity we get from a battery, the flow of current is in one direction only.

В) direct

Earthing is brought about by connecting the metal body or frame directly to.... 6) earth

Ek'clricity and -.. are closely connected. a) magnetism

Electricity flowing ihrough a conductor may be likened to water flowing through a.... б) pipe

Every additional resistance in parallel will reduce the total... of a circuit. в) resistance

Every component in series in a circuit will add to the total resistance of the circuit and decrease the... flowing through it. 6) cuiient

... has a nnich lower resistance than other common metals. в) copper

If a conductor is made to rotate in a magnetic field, a pressure of electricity, called a.... is produced in it. 6) voltage

If lightning strikes the building, the charge is conducted safely to.... a) earlh

If the number of turns in the secondary winding is greater than the number in the primary, it is a... transformer. г) step-up

In a radio the valve allows the flow of electrons from cathode to.... a) anode

In a three-pin power plug the thickest... is always the earth connection. в) pin

Insulation, earthing, fuses and automatic cutouts are among the most common... devices. д) safety

Insulating is the converting of a conductor with a non-conducting material to prevent it from touch ing another.... a) conductor

It is cheaper and easier to carry a veiyhigh... but low current, over long distances. г) voltage

It is convenient and economical lo operate electronic apparatus from a.... в) distance

It is very impoilant lhat fuse wire of the correct... is used. 6) amperage

It is often necessary to increase or... the voltage of electricity supply. в) decrease

Large switches which are used for high voltages are known as circuit.... a) breakers

Many precautions are taken and safety... are used to minimize electric dangers. г) devices

... materials are used to cover and protect conductor wires and sometimes to separate them,

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