# Physics MCQ (Multiple Choice Questions) - SchoolingAxis

Que- If the distance between the two point charges become half then force between them becomes

a. double

b. half

c. four times

d. remains same

Que- The minimum charge on any object cannot be less than

a. 1.6 x 10-19C

b. 3.2 x 10-19C

c. 9.1 x 109C

d. no definite value exist

Que- Electric charge of 100 ?C is 13cm apart from another charge 16.9 Degree C electric force between them is

a. 9x107N

b. 900N

c. 9x105N

d. 9x106N

Que- Electric force between two point charges in air or vacuum is F. If we replace air or vacuum by an insulator (dielectric) of relative permitivity Cr the force between the charges will

a. decrease

b. increase

c. remain constant

d. depends upon composition of dielectric

Que- Two charges are placed at a certain distance. If the magnitude of each charge is doubled the force will become

a. 1/4th of its original value

b. 1/8th of its original value

c. 4 times of its original value

d. 8 times of its original value

Answer- 4 times of its original value

Que- The force per unit charge is know as

a. electric flux

b. electric intensity

c. electric potential

d. all of above are same

Que- An electric field can deflect

a. neutrons

b. X-rays

c. both glass rod and silk acquire negative charge

d. none

Que- An electric charge at rest produces

a. only a magnetic field

b. only an electric field

c. neither electric field nor magnetic field

d. both electric and magnetic fields

Que- Tick the only wrong statement.

a. similar charges repel each other

b. dissimilar charges attract each other

c. repulsion is the sure test of electrification

d. an electrically neutral body is repelled both positively and negatively charged bodies

Answer- an electrically neutral body is repelled both positively and negatively charged bodies

Que- Electric intensity being a vector quantity always points

a. along the direction of force experienced by a unit positive charge

b. opposite to the direction of force experienced by a unit positive charge

c. perpendicular to the direction of force experienced by a uit positive charge

d. any of above

Answer- along the direction of force experienced by a unit positive charge

Que- Electric flux linked with a surface will be maximum when

a. the surface is held parallel to the electric field

b. the surface is held perpendicular to the electric field

c. the surface makes an angle of 45 Degree with the field

d. all of the above

Answer- the surface is held perpendicular to the electric field

Que- A closed surface contains two equal and opposite charges. The net electric flux from the surface will be

a. negative

b. positive

c. zero

d. data is insufficient

Que- The electric lines of force are

a. imaginary

b. physically existing every where

c. physically existing near the charges

d. depends upon case

Que- Tick the correct statement

a. the electric lines of force have no physical existence

b. they expand laterally and contract longitudinally

c. they do not cross each other and group together in dielectric

d. all the above statements are true

Answer- all the above statements are true

Que- If free space between the plates of a capacitor is replaced by a dielectric

a. The potential difference remains constant capacittance and energy stored increases

b. The potential difference remains constant capacittance decreases and energy increases

c. The potential difference decreases but both capacitance and energy increase

d. both potential difference and capacitance decrease but energy increases

Answer- The potential difference decreases but both capacitance and energy increase

Que- Two similar charges each of one coulomb placed in air one meter apart repel each other with a force

a. 9 x 109N

b. 9.2 x 104N

c. 9 x 109N

d. 9 x 107N

Que- A hollow metallic sphere of 8cm diameter is charged with 4 x 10 8

a. The potential on its surface will be

b. 900 volts

c. 9000 volts

d. 90 volts

Que- The metallic spheres A and B of radii 2m and 4m respectively carry the same charge 4 x 10 8

a.  If the spheres are connected by a copper wire

b. charge will flow from A to B

c. charge will flow from B to A

d. no flow of charge will occur

Answer-  If the spheres are connected by a copper wire

Que- Potential difference is the work done in moving unit positive charge form one point to another

a. in the direction of electric intensity

b. against electric intensity

c. in any direction

d. in the direction of electric flux

Que- Equipotential planes are

a. parallel to one another

b. non parallel to one another

c. intersecting

d. circular

Que- The value of the capacitance depends upon the

a. voltage applied

b. thickness of the capacitor plates

c. geometry of the capacitor

d. dinsity of the capacitor plates

Que- A 25eV electron has a speed of

a. 2 x 106m/sec

b. 3 x 106m/sec

c. 5 x 106m/sec

d. 4 x 106m/sec

Que- A 5 Degree F capacitor has a potential difference across its plates of 200 volts. The charge on the capacitor is

a. 2.5 x 10-8 C

b. 10-5 C

c. 103 C

d. 4 x 103 C

Que- capacitor is to have an energy content of 20J it must be placed across a potential difference of

a. 4 volts

b. 9 volts

c. 2 volts

d. 1 vol

Que- Equivalent capacitance is greater than individual capacitances in

a. series combination

b. parallel combination

c. both series and parallel combinations

d. none of above

Que- Two oppositely charged balls A and B attract third conducting ball C when placed near them turn by turn. Then ball C must be

a. positively charged

b. electrically neutral

c. negatively charged

d. positively and negatively charged

Que- The number of electrons in one coulomb charge is equal to

a. 6.2 x 1018

b. 1.6 x 1019

c. 6.2 x 1021

d. 1.6 x 10-27

Que- In a non-uniform electric field a polar molecule will experience

a. Net torque

b. Net force

c. both series and parallel combinations

d. zero

Answer- both series and parallel combinations

Que- SI unit of permitivity of free space is

a. Nm2C2

b. N-1mC-2

c. NmC-1

d. N-1m-2C2

Que- Value of ?r for various dielectrics is always

a. less than unity

b. equal to unit

c. larger than unit

d. no hard and fast rule

Que- Electric intensity at infinite distance from the point charge is

a. zero

b. infinite

c. positive

d. negative

Que- N/C =

a. V/A

b. J/V

c. V/m

d. A/m

Que- A charge of 0.10C accelerated through a potential difference of 1000V acquires kinetic energy

a. 200J

b. 100J

c. 1000J

d. 100 eV

Que- A capacitor is a perfect insulator for

a. direct current

b. alternating current

c. both for the direct and alternating current

d. none of above

Que- Three capacitors C1 C2 and C3 are connected in parallel as in the Fig. The equivalent capacitance will be

a. 8 Degree F

b. 0.8 Degree F

c. 1 Degree F

d. 16 Degree F

Que- In a charged capacitor the energy resides in

a. magnetic hield

b. electric field

c. nuclear field

d. gravitational field

Que- Selenium becomes a conductor in light so it behaves like

a. Semiconductor

b. Photodiode

c. Light emitting diode

d. Capacitor

Que- Photocopier and inject printer are dealt in

a. Electrostatics

b. Charges in motion

c. Capacitors

d. Electric fields

Que- If a charged rod is brought closer to a gas filled balloon then

b. Balloon bursts

d. Balloon squeezes

Que- If metallic conductor is charged negatively then its weight

a. Remains same

b. First increases then decreases

c. Decreases then increases

d. Increases for a while

Que- If mica sheet is placed between the plates of a capacitor the capacity

a. increases

b. decreases

c. increases then decreases

d. decreases then increases

Que- If two charges are increased by two times then force

a. Decreases 9 times

b. Increases 9 times

c. Increases 4 times

d. Decreases 4 times

Que- If an electrons is allowed to move along the field in a non uniform electric field then it will follow

a. Spiral path

b. Straight line

c. Curved path

d. Circular path

Que- The current through a metallic conductor is due to the motion of

a. free electrons

b. protons

c. neutrons

d. still under controversy

Que- Resistance of a conductor depends upon

a. nature of conductor

b. dimension of conductor

c. physical state of the conductor

d. all of above

Que- A wire having very high value of conductance is said to be

a. very good conductor

b. moderately good conductor

c. an insulator

d. no specific criterion available

Que- A wire of uniform area of cross-section A length L and resistance R is cut into two parts. Resistivity of each part

a. remains the same

b. is doubled

c. is halved

d. becomes zero

Que- Production of heat due to an electric current flowing through a conductor is given by

a. Joule effect

b. Joule Thomsons effect

c. Comptons effect

d. Feed back effect

Que- When same current passes for same time through a thick and thin wire

a. more heat is produced in thick wire

b. more heat is produced in thin wire

c. no heat is produced in wire

d. less heat is produced in thick wire

Answer- more heat is produced in thin wire

Que- Three equal resistors connected in series with a source of e m f together dissipate 10 W of power each. What will be the power dissipated if the same resistors are connected in parallel across the same source of e m f?

a. 40 W

b. 90W

c. 100W

d. 120W

Que- One kilowatt hour is the amount of energy delivered during

a. one second

b. one day

c. one minute

d. one hour

Que- Thermocouples convert

a. heat energy into electrical energy

b. heat energy into light energy

c. heat energy into mechanical energy

d. mechanical energy into heat energy

Answer- heat energy into electrical energy

Que- How much heat does a 40 W bulb generates in one hour?

a. 144000J

b. 144J

c. 1.44J

d. 14J

Que- An immersion heater of 400 watts kept on for 5 hours will consume electrical power of

a. 2KWh

b. 20KWh

c. 6KWh

d. 12KWh

Que- Resistance of a super conductor is

a. finite

b. infinite

c. zero

d. changes with every conductor

Que- Resistance of an ideal insulator is

a. infinite

b. zero

c. finite

d. depends upon nature

Que- Which one is the best material for making connecting wires?

a. iron

b. tungsten

c. silver

d. copper

Que- Reciprocal of resistivity is called

a. resistance

b. inductance

c. conductivity

d. flexibility

Que- Circuit which gives continuously varying potential is called

a. complex network

b. wheat stone bridge

c. potential divider

d. all of above

Que- Internal resistance is the resistance offered by

a. source of e m f

b. conductor

c. resistor

d. capacitor

Answer- source of e m f

Que- There are three bulbs of 60W 100W and 200W which bulb has thickest filament.

a. 100W

b. 200W

c. 60W

d. all

Que- Three bulbs are rating 40W 60W and 100W designed to work on 220V mains. Which bulb will burn most brightly if they are connected in series across 220 V mains?

a. 40 W bulb

b. 60 W blub

c. 100 W blub

d. all will burn equally brightly

Que- Resistance of a wire on increasing its temperature will

a. increase with rise in temperature

b. decrease with rise in temperature

c. will remain same

d. depends upon altitude of experimentation

Answer- increase with rise in temperature

Que- Specific resistance of a wire

a. will depend on its length

b. will depend on its radius

c. will depend on the type of material of the wire

d. will depend on none of the above

Answer- will depend on the type of material of the wire

Que- An electric iron is marked 20 volts 500W. The units consumed by it in using if for 24 hours will be

a. 12

b. 24

c. 5

d. 1100

Que- In liquids and gases the current is due to the motion

a. negative charges

b. positive charges

c. both negative and positive charges

d. neutral particles

Answer- both negative and positive charges

Que- If 1 ampere current flows through 2m long conductor the charge flow through it in 1 hour will be

a. 3600C

b. 7200C

c. 1C

d. 2C

Que- The graphical representation of Ohms law is

a. hyperbola

b. ellipse

c. parabola

d. straight line

Que- Which one of the following materials is useful for making bulb filaments?

a. constantan

b. nichrome

c. copper

d. tungsten

Que- The resistance of a conductor at absolute zero (OK) is

a. zero almost

b. infinite almost

c. no prediction at all

d. may increase or decrease

Que- Why should a resistance be introduced in a circuit in series deliberately?

a. to increase current

b. to decrease current

c. to control current

d. just to give a good look to circuit

Que- Electrical energy is measured in

a. watt

b. horse power

c. kilo watt

d. kilowatt hour

Que- All electrical appliances are connected in parallel to each other between the main line and neutral wire to get

a. same current

b. same current and potential difference

c. different current but same potential difference

d. different current and potential differences

Answer- different current but same potential difference

Que- Electrical energy is converted to heat at the rate of

a. IRt

b. I2R

c. I2Rt

d. VIt

Que- Which one of the following bulbs has the least resistance?

a. 100 watt

b. 200 watt

c. 300 watt

d. 60 watt

Que- A fuse is placed in series with the cireuit to protect against

a. high power

b. high voltage

c. high current

d. over heating

Que- Terminal potential difference of a battery is greater than its emf when

a. the internal resistance of battery is infinite

b. the internal resistance of battery is zero

c. the battery is charged

d. the battery is discharged

Que- Magnetic force acting on a unit positive charge moving perpendicular to the magnetic field with a unit velocity is called

a. magnetic flux

b. magnetic field intensity

c. magnetic induction

d. self inductance

Que- What is the value of the current in a wire of 10cm long at the right angle to a uniform magnetic field of 0.5 Weber/m2 when the force acting on the wire is 5N?

a. 1A

b. 10A

c. 100A

d. 1000A

Que- When a particle of charge q and mass m enters into a uniform magnetic field B moving with a velocity v perpendicular to the direction for the field it describes a circular path of radius

a. R=qB/mV

b. R=mV/qB

c. R=qmV/B

d. R=qmB/V

Que- Two parallel wires carrying currents in the opposite directions

a. repel each other

b. attract each other

c. have no effect upon each other

d. they cancel out their individual magnetic fields

Que- A magnetic compass will be deflected if it is kept near a

a. charge in motion

b. charge at rest

c. both

d. none

Que- A magnetic field

a. always exerts a force on a charged particle

b. never exerts a force on a charged particles

c. exerts a force if the charged particle is moving in the direction of the magnetic field lines

d. exerts a force if the charged particle is moving perpendicular to the magnetic field lines

Answer- exerts a force if the charged particle is moving perpendicular to the magnetic field lines

Que- A moving coil galvanometer of resistance 100 ohm gives half scale deflection for a current of 20mA. What will be the potential difference across it?

a. 4 volt

b. 5 volt

c. 2 volt

d. 0.4 volt

Que- Which one of the following material is most suitable for making core of an electromagnet?

a. air

b. steel

c. Cu-Ni alloy

d. soft iron

Que- The magnetic force experienced by a charge particle moving in a magnetic field will be minimum when it moves

a. perpendicular to the field

b. parallel to the field

c. inclined parallel to the field

d. at an angle of 45 Degree

Que- The relationship between Tesla and smaller unit Gauss of magnetic induction is given by

a. 1T = 103 G

b. 1T = 10-4 G

c. 1T = 10-2 G

d. 1T = 104 G

Que- SI unit of flux density is

a. NA-1m-1

b. NAm-1

c. NmA-1

d. NmA-2

Que- Magnetic flux and flux density are related by

a. magnetic flux = flux density / area

b. magnetic flux = flux density x area

c. flux density = magnetic flux area

d. flux density = magnetic flux x area

Answer- magnetic flux = flux density x area

Que- The standard vector symbol for flux density is

a. "M"

b. "L"

c. "H"

d. "B"

Que- The charged particle enters the uniform magnetic field in such a way that its initial velocity is not perpendicular to the field the orbit will be

a. a circle

b. a spiral

c. an ellipse

d. helix

Que- An electron enters a region where the electric field E is perpendicular to the magnetic field

a. It will suffer no deflection if

b. E = BeV

c. B = eE/V

d. E = BV

Que- An instrument which can measure potential without drawing any current is

a. voltmeter

b. galvanometer

c. cathode ray oscilloscope (CRO)

d. ammeter

Que- The deflection for 50 division of galvanometer is decreased to 25 divisions by shunt resistance of 12 ohm. Galvanometer resistance is

a. 18 ohm

b. 30 ohm

c. 24 ohm

d. 12 ohm

Que- When the coil of the galvanometer is in equilibrium then the deflecting couple is

a. zero

b. equal to the restoring couple

c. greater than the restoring couple

d. smaller than the restoring couple

Answer- equal to the restoring couple

Que- The sensitivity of a galvanometer is given by

a. C/BAN

b. CAN/B

c. BAN/C

d. ABC/N

Que- Which one of the following is not an electromechanical instrument?

a. galvanometer

b. voltmeter

c. ammeter

d. AC transformer and DC generator

Answer- AC transformer and DC generator

Que- Minimum current required to produce a deflection of 1 mm on a scale at a distance of 1 meter is

a. 0.1 A

b. 1:00 AM

c. current sensitivity

d. 1 m A

Que- In a multi range ammeter as the range increases

a. shunt value decreases

b. shunt value increases

c. shunt value remains the same

d. none of the above

Que- While measuring the unknown resistance the help of slide wire  bridge a greatest accuracy can be achieved when

a. a most sensitive galvanometer is used

b. a steady voltage cell is used

c. the balance point is close to the middle of the wire

d. a high resistance box is used in one of its gap

Answer- the balance point is close to the middle of the wire