MAGNETISM

• The phenomenon related to attractive and directive properties is:

Answer :  Magnetism

• Attraction is the surest test of magnetism:

Answer :  False

• Like poles of a magnet repel each other:

Answer :  True

• Materials which are attracted by magnets are:

Answer :  Ferromagnetic

• Which is not a ferromagnetic material:

Answer :  Glass

• Which is a ferromagnetic material:

Answer :  Cobalt

• Properties of a magnet are:

Answer :  attractive and directive;

• In a magnet, the attraction is strongest

Answer :  at poles

• Freely suspended magnet points in ____ direction

Answer :  north-south

• Iron loses its magnetism easily.

Answer :  True

• Steel is a hard magnetic material.

Answer :  True

ELECTROMAGNETISM

• Solenoid with soft iron core is:

Answer :  electro magnet

• A coil wound over soft iron piece is:

Answer :  Solenoid

• An electro magnet is:

Answer :  temporary magnet

• When current through coil stops flowing, the coil remains an electromagnet.

Answer :  False

• Steel is used to make permanent magnet.

Answer :  True

• The magnetic field around a current carrying coil

Answer :  Lasts as long as current flows

• Strength of magnetic field in solenoid can be increased by:

Answer :  increasing the number of turns

• Which is not a use of electromagnet

Answer :  study mechanical properties of magnets

• Which are uses of electromagnet:

Answer :  lifting and transporting large weights and removing pieces of iron from wounds

• Strength of an electromagnet can be determined using:

Answer :  magnetic compass

ELECTRIC BELL

• A device that works on the basis of magnetic effects of current:

Answer :  electric bell

• In an electric bell:

Answer :  electrical energy is converted to sound energy

• Electric bell is application of:

Answer :  electromagnet and magnetic effect of current

• Which is incorrect for working of electric bell?

Answer :  the bell rings when switch is not pressed

• Which is correct for working of electric bell?

Answer :   process of make and break of circuit goes on and  hammer strikes the gong repeatedly

• In electric bell, when electromagnet is demagnetised, the hammer strikes the gong:

Answer :  False

• On magnetisation of electromagnet the hammer of electric bell strikes gong.

Answer :  True

• Magnet used in electric bell is:

Answer :  horse shoe electromagnet

SERIES CIRCUIT

• Switch is always connected to live wire.

Answer :  True

• When there is a break in path of current, circuit is called:

Answer :  open circuit

• In series circuit, each device is connected in such a manner that there is only one path for current:

Answer :  True

• Which is incorrect for series circuit:

Answer :  circuit has two or more paths

• Which is correct for series circuit:

Answer :  voltage is same across each component and a break in circuit stops all current

• Series circuit has only one path for electrons to flow

Answer :  True

• Formula of Total Series Resistance is ___

Answer :  RT = R1 + R2 + R3

• Total resistance of R1=20 ohm, R2=57 ohm and R3=90 ohm in series is:

Answer :  167 ohm

• Total resistance of R1=200 ohm, R2=40 ohm and R3=60 ohm in series is:

Answer :   300 ohm

• Total power in series circuit is ___ of  individual powers.

Answer :  Sum

• Batteries are generally connected in:

Answer :  Series

• In series circuit if one bulb goes out, others will:

Answer :  also turn off

• Addition of resistances in series circuit increases net resistance.

Answer :  True

PARALLEL CIRCUIT

• In a parallel circuit, there are two or more paths for current to flow.

Answer :  True

• Which is correct for parallel circuit:

Answer :  Voltage is same across each component of circuit and a break in branch stops current in the branch

• Which is incorrect for parallel circuit:

Answer :  there is only one path for current

• Total Resistance when, 470 Ω, 220 Ω, and 100 Ω are all in parallel.

Answer :  60 Ω

• Sudden increase in total current in a parallel circuit may indicate

Answer :  increase in source voltage

• Five 100 Ω resistors are connected in parallel. If one resistor is removed, total resistance is:

Answer :  25 Ω

• It is preferable to connect bulbs in:

Answer :  Parallel

• In ____ connection total resistance is smaller than the smallest resistance.

Answer :  Parallel

• Total resistance in parallel circuit is:

Answer :  1/Rt = 1/R1 + 1/R2 + 1/R3 +…

• In parallel circuit branch with lowest resistance has maximum current.

Answer :  True

• Current in each path of parallel circuit is always same.

Answer :  False

• Voltage in each path of parallel circuit is always same.

Answer :  True

• Addition of resistances in a parallel circuit increases net resistance.

Answer :  False

• In ___ Circuit, current is same in all parts.

Answer :  Series

• Total resistance of circuit is equal to sum of individual resistances in-

Answer :  Series Circuit

• In ____ connection total resistance is larger than the largest resistance.

Answer :  Series

ELECTRICITY

• Which is electricity effect:

Answer :  Heating effect and Magnetic effect

• Electric appliances where heating effect of electric current is not used:

Answer :  Fan

• Copper and aluminium wires are usually employed for electricity transmission because

Answer :  they have low resistance and they are strong

• Full form of CFL:

Answer :  Compact Fluorescent Lamp

• Full form of LED:

Answer :  Light Emitting Diode

• Devices which deliver electricity are called:

Answer :  Source

• Devices which consume electricity are called

Answer :  Load

• Electric generator converts:

Answer :  mechanical energy to electrical energy

• Solar cell converts:

Answer :  solar energy to electrical energy

• Combination of solar cells forms:

Answer :  solar panel

• Solar cells are used by satellites in space for generation of electricity

Answer :  True

• Tungsten is used for filament of electric lamp because of

Answer :  high melting point and high resistance

• Filament of electric bulb is made of:

Answer :  Tungsten

• Electric current is flow of ____:

Answer :  Electrons

• All wires in electric circuit should be covered with:

Answer :  Insulators

• The bodies which allow current to pass through them are:

Answer :  Conductors

• The main component of electric circuit:

Answer :  electric cell

• Pure water is good conductor of electricity:

Answer :  False

• When circuit is closed electric current does not flow:

Answer :  False

• Our body is _____ of electricity:

Answer :  Conductor

• Electric fuse is used to protect household electric appliances from accidental

Answer :  Large flow of current

• Unit of electrical resistance

Answer :  Ohm

• Device use to make or break circuit:

Answer :  Switch

• Path along which electric current flows is called ______.

Answer :  Circuit

• Current does not flow in ____ circuit.

Answer :  Open

• In a cell, electrons flow from ___ terminal to ___ terminal.

Answer :   negative to positive

• Electric cell produces electricity from _____ stored in it.

Answer :  chemicals stored in it

• A combination of two or more cells is called.

Answer :  Battery

• In a dry cell:

Answer :  chemical energy changes to electric energy

• Primary cells are used in:

Answer :  Torches

• Secondary cells are used in:

Answer :  mobile phones

• Dry cell can be reused

Answer :  False

• Secondary cell are rechargeable.

Answer :  True