CBSE Class 12 Physics Quiz! Test
(156).jpg "CBSE Class 12 Physics Quiz! Test - Quiz")
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- 1.
The name electricity is coined from the Greek word __________meaning amber
- A.
Elektron
- B.
Electron
- C.
Electrion
- D.
Elektrion
Correct Answer
A. ElektronExplanation
Elektron is a greek word that coins electricityRate this question:
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- 2.
_______________ offer resistance to the movement of charges which is intermediate between the conductors and insulators.
- A.
Dielectric
- B.
Nonconductors
- C.
Semiconductors
- D.
Nonmetals
Correct Answer
C. SemiconductorsExplanation
They have temperature dependent characterticsRate this question:
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- 3.
The degree of _____________ is an indicator of the amount of charge.
- A.
Polarity
- B.
Divergence
- C.
Positive charge
- D.
Negative charge
Correct Answer
B. DivergenceExplanation
When a charged object touches the metal knob at the top of the rod, charge flows on to the leaves and theyRate this question:
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- 4.
Charge,e =
- A.
1.602192 × 10^–9 C
- B.
1.602192 × 10^–19 C
- C.
1.602192 × 10^+19 C
- D.
1.602192 × 10^+9 C
Correct Answer
B. 1.602192 × 10^–19 CExplanation
one coulomb is the charge flowing through a wire in 1 s if the current is 1 A (ampere)Rate this question:
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- 5.
Coulomb used a torsion balance. A torsion balance is a sensitive device to measure ________.
- A.
Charge
- B.
Elecricity
- C.
Polarity
- D.
Force
Correct Answer
D. ForceExplanation
Coulomb used torsion balance only for measuring the force between two charged metallic spheresRate this question:
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- 6.
The charge q, which tests the effect of a source charge, is called___________
- A.
Postive Charge
- B.
Negative charge
- C.
Auxilary charge
- D.
Test charge
Correct Answer
D. Test chargeExplanation
The source charge Q must remain at its original locationRate this question:
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- 7.
Electric field is a --------------field, since force is a------------ quantity
- A.
Vector,Vector
- B.
Scalar,Vector
- C.
Vector,Scaler
- D.
Scalar,Scalar
Correct Answer
A. Vector,VectorExplanation
"The term field in physics generally refers to a quantity that is
defined at every point in space and may vary from point to point."Rate this question:
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- 8.
The picture of field lines was invented by Faraday,called---------
- A.
Line of Field
- B.
Line of force
- C.
Line of charge
- D.
Line of falls
Correct Answer
B. Line of forceExplanation
"The picture of field lines was invented by Faraday to develop an
intuitive non- mathematical way of visualizing electric fields around charged configurations. Faraday called them lines of force."Rate this question:
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- 9.
Two field lines can never cross each other.
- A.
True
- B.
False
Correct Answer
A. TrueExplanation
"If they did, the field at the point of intersection will not have a
unique direction, which is absurd."Rate this question:
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- 10.
The field of the electric dipole is--------
- A.
Zero
- B.
Notzero
- C.
Uncertain
- D.
Infinity
Correct Answer
B. NotzeroExplanation
The total charge of the electric dipole is obviously zero. This does notmean that the field of the electric dipole is zeroRate this question:
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- 11.
A plane perpendicular to the dipole axis through its centre.
- A.
S-plane
- B.
Xy plane
- C.
Perpendicular plane
- D.
Equatorial plane
Correct Answer
D. Equatorial planeExplanation
The equatorial plane of the dipole,i.e., on a plane perpendicular to the dipole axis through its centre.Rate this question:
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- 12.
The centres of positive charges and of negative charges lie at the same place,their dipole moment is -----------.
- A.
Uncertain
- B.
Zero
- C.
Not zero
- D.
Infinity
Correct Answer
B. ZeroExplanation
In most molecules, the centres of positive charges and of negative charges lie at the same place. Therefore, their dipole moment is zero.Rate this question:
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- 13.
The volume charge density also called as -----------
- A.
Field density
- B.
Volume density
- C.
Charge density
- D.
Charged density
Correct Answer
C. Charge densityExplanation
sometimes simply called charge densityRate this question:
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- 14.
∆s Denotes---------
- A.
Vector area element
- B.
Electric field
- C.
Electric flux
- D.
Electric charge
Correct Answer
A. Vector area elementExplanation
According to physical quantity it denotes vector area elementRate this question:
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- 15.
Linear Charge density is --,surface Charge density is --,volume Charge density is --.
- A.
ρ,λ,σ
- B.
λ,ρ,σ
- C.
λ,σ,ρ
- D.
σ,ρ,λ
Correct Answer
C. λ,σ,ρExplanation
conventional symbolsRate this question:
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- 16.
Coulomb force and gravitational force follow the same ----------
- A.
Square law
- B.
Inverse square law
- C.
Inverse law
- D.
Newton's law
Correct Answer
B. Inverse square lawExplanation
Coulomb force and gravitational force follow the same inverse-square lawRate this question:
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- 17.
Superposition principle,there are ----additional three-body, four-body, etc., forces which arise only when there are more than two charges
- A.
Few
- B.
No
- C.
More
- D.
None of the above
Correct Answer
B. NoExplanation
Based on Superposition principle.Rate this question:
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- 18.
"The electric field due to a charge configuration with total charge zero is not zero; but for distances large compared to the size of the configuration, its field falls off faster than 1/r2, typical of field due to a single charge".Give example for above fact.
- A.
Electric charge
- B.
Electirc density
- C.
Electric dipole moment
- D.
Electric dipole
Correct Answer
D. Electric dipoleExplanation
An electric dipole is the simplest exampleRate this question:
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- 19.
In a non-polar molecule, the centres of positive and negative charges coincide.
- A.
FALSE
- B.
TRUE
Correct Answer
B. TRUEExplanation
Nature of non-polar molecules.Rate this question:
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- 20.
Two large plane parallel conducting plates separated by a small distance.
- A.
Parallel plane capacitors
- B.
Serial plate capacitors
- C.
Parallel plate capacitors
- D.
Serial plane capacitors
Correct Answer
C. Parallel plate capacitorsExplanation
A parallel plate capacitor consists of two large plane parallel conducting plates.Rate this question:
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- 21.
Which is typically the order of magnitude of currents in domestic appliances?
- A.
Ampere
- B.
Field
- C.
Mobility
- D.
Voltage
Correct Answer
A. AmpereExplanation
An ampere is defined through magnetic effects of currentsRate this question:
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- 22.
A gram of water contains approximately 10^22 ------------
- A.
Electrons
- B.
Charged nuclei
- C.
Atom
- D.
Molecules
Correct Answer
D. MoleculesExplanation
Bulk matter is made up of many molecules.Rate this question:
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- 23.
A basic law regarding flow of currents was discovered by------------in 1828, long before the physical mechanism responsible for flow of currentswas discovered.
- A.
Faraday
- B.
G.S. Ohm
- C.
Van de Graff
- D.
Kirchoff
Correct Answer
B. G.S. OhmExplanation
based on ohm's bibliographyRate this question:
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- 24.
I/A, is called --------
- A.
Current intensity
- B.
Magnetic field density
- C.
Current density
- D.
Magnetic field density
Correct Answer
C. Current densityExplanation
j= I/A (i.e) current densityRate this question:
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- 25.
The collisions of the electrons occur at regular intervals
- A.
False
- B.
True
Correct Answer
A. FalseExplanation
"since, the direction of the velocity of an electron is completely
random."Rate this question:
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- 26.
Relaxation time is denoted using---------
- A.
σ
- B.
τ
- C.
λ
- D.
ρ
Correct Answer
B. τExplanation
Standard denotion.Rate this question:
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- 27.
Give an example of a material exhibiting behaviour such as relation between V and I is not unique
- A.
Glass
- B.
Pure water
- C.
NaCl
- D.
GaAs
Correct Answer
D. GaAsExplanation
In GaAs,there is more than one value of V for the same current IRate this question:
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- 28.
Which exhibit a very weak dependence of resistivity with temperature?
- A.
Nickel
- B.
Pure water
- C.
Nichrome
- D.
Iron
Correct Answer
C. NichromeExplanation
which is an alloy of nickel, iron and chromium.Rate this question:
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- 29.
State Ohmic loss
- A.
VxI
- B.
I^2 x R
- C.
IV∆t
- D.
IxR
Correct Answer
B. I^2 x RExplanation
Using ohm's law P=I^2 x RRate this question:
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- 30.
Emf is __________
- A.
Electromotive force
- B.
Electromagnetic force
- C.
Electromechnical force
- D.
Electricmechical force
Correct Answer
A. Electromotive forceExplanation
General abbrevationRate this question:
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- 31.
Kirchhoff’s rules
- A.
Junction rule & loop rule
- B.
Junctional rule & loop rule
- C.
Mesh rule & node rule
- D.
Loop rule & node rule
Correct Answer
A. Junction rule & loop ruleExplanation
Termed as junction & loop rule.Rate this question:
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- 32.
The ------------ and its balance condition provide a practical method for determination of an unknown resistance
- A.
Ammetre
- B.
Potentiometre
- C.
Metre bridge
- D.
Wheatstone bridge
Correct Answer
D. Wheatstone bridgeExplanation
It only uses balance condition to find the resistanceRate this question:
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- 33.
Which one of these is used to measure internel resitance of a cell
- A.
Wheatstone bridge
- B.
Ammetre
- C.
Potentiometre
- D.
Metre bridge
Correct Answer
C. PotentiometreExplanation
For this the cell (emf e ) whose internal resistance (r) is to be determined isconnected across a resistance box through a key K2.Rate this question:
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- 34.
__________= 1V/A
- A.
1℮
- B.
1Ω
- C.
1ρ
- D.
1σ
Correct Answer
B. 1ΩExplanation
unit of resistance.Rate this question:
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- 35.
The algebraic sum of changes in potential around any closed loop must be-----
- A.
Negative
- B.
Positive
- C.
Zero
- D.
All the above
Correct Answer
C. ZeroExplanation
based on loop rule.Rate this question:
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- 36.
Current is a Vector Quantity
- A.
FALSE
- B.
TURE
Correct Answer
A. FALSEExplanation
Current is a scalar although we represent current with an arrow.Rate this question:
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- 37.
silver is a ---------conductor
- A.
Non
- B.
Heterogeneous
- C.
Non-Homogeneous
- D.
Homogeneous
Correct Answer
D. HomogeneousExplanation
silver consists of homogeneous molecules.Rate this question:
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- 38.
Kirchhoff’s --------- is based on conservation of charge
- A.
Loop rule
- B.
Junction rule
- C.
Loop & junction rule
- D.
Either junction or loop rule
Correct Answer
B. Junction ruleExplanation
since Bending or reorienting the wire does not change the validity of Kirchhoff’s junction rule.Rate this question:
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- 39.
A current or a field (electric or magnetic) emerging out of the plane of the paper is depicted by -----
- A.
Dot
- B.
Cross
- C.
Both dot & cross
- D.
Neither cross nor dot
Correct Answer
A. DotExplanation
According dot rule.Rate this question:
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- 40.
The radius of the circular component of motion is called the radius of the -------.
- A.
Rectangular
- B.
Circular
- C.
Helix
- D.
Hyperbola
Correct Answer
C. HelixExplanation
Due to generic motionRate this question:
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- 41.
The cyclotron uses----------- to increase the energy of charged particles.
- A.
Electric field
- B.
Magnetic field
- C.
Magnetostatic field
- D.
Both electric &magnetic fields
Correct Answer
D. Both electric &magnetic fieldsExplanation
both electric and magnetic fields in combination is used to increase the energy of charged particles.Rate this question:
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- 42.
In cyclotron, as the fields are perpendicular to each other are called ------------
- A.
Perpendicular field
- B.
Crossed fields
- C.
Cyclotron field
- D.
Magnetic field
Correct Answer
B. Crossed fieldsExplanation
There are generally called as crossed fields.Rate this question:
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- 43.
VECC is------
- A.
Variable energy cyclotron center
- B.
variation energy cyclotron center
- C.
Variant energy cyclotron center
- D.
Various energy cyclotron center
Correct Answer
A. Variable energy cyclotron centerExplanation
Since the variable energy cyclotron was build in VECC, kolkata.Rate this question:
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- 44.
In Biot-Savart’s law the relation between --------- and ------- field it produces.
- A.
Current & electric
- B.
Current & magnetic
- C.
Electric & magnetic
- D.
Magnetic& dielectric
Correct Answer
B. Current & magneticExplanation
based on biot savart law's statementRate this question:
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- 45.
According to amperain loop, B is -----------
- A.
Only tangential
- B.
Only normal
- C.
Tangential or normal
- D.
Both tangential and normal
Correct Answer
C. Tangential or normalExplanation
based on assumption made in amperian loop B is tangetial or normal or vanish.Rate this question:
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- 46.
Ampere's circuital law holds for----------
- A.
Steady current
- B.
Steady voltage
- C.
Flucuating current
- D.
Flucuating voltage
Correct Answer
A. Steady currentExplanation
According to ampere circuital alwRate this question:
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- 47.
Television uses the --------- to generate the magnetic fields needed.
- A.
Toroid or solenoid
- B.
Both solenoid & toroid
- C.
Toroid
- D.
Solenoid
Correct Answer
D. SolenoidExplanation
Television only uses solenoid.Rate this question:
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- 48.
Parallel currents repel, and anti-parallel currents attract.
- A.
TRUE
- B.
FALSE
Correct Answer
B. FALSEExplanation
opppositely directed currents repel each other.Rate this question:
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- 49.
The resembalance of magnertic field lines for abar magnet and a ------------- suggest that a bar magnet may be thought of as a large number of circulating current in analogy with a ----------. HINT:bar magnet as an equalent solenoid.
- A.
Solenoid, toroid
- B.
Toroid,toroid
- C.
Solenoid,solenoid
- D.
Toroid, solenoid
Correct Answer
C. Solenoid,solenoidExplanation
bar magnet as an equalent solenoid.Rate this question:
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- 50.
The magnet field lines gives us an approximate idea of the magnetic field B.
- A.
Pattern of electric fillings
- B.
Pattern of magnetic fillings
- C.
Pattern of dipole fillings
- D.
Pattern of iron fillings
Correct Answer
D. Pattern of iron fillingsExplanation
A dipole in an uniform magnetic field.Rate this question:
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