Lenz's law is the consequence of the law of conservation of
Energy
Charge
Field lines
Momentum
Correct Answer :
A. Energy
Related Questions
The magnetic energy stored in an inductor is ______ current.
Directly proportional to
Inversely proportional to
Directly proportional to the square of
Inversely proportional to the square of
The flux density in an air-cored coil is 10^-3 Wb/m^2. With a cast iron core of relative permeability 100 inserteda the flux density will become
10^-3 Wb/m^2
10^-2 Wb/m^2
10^3 Wb/m^2
0.1 Wb/m^2
The emf induced in a coil due to the changing current of another neighboring coil is called
Mutually induced emf
Self induced emf
Statically induced emf
Dynamically induced emf
What bond is formed when one or more electrons in the outermost energy orbit of an atom are transferred to another?
Ionic
Covalent
Metallic
Van der Waals
What is the unit of reluctance?
Maxwell
Gauss
At/Wb
Weber
The force acting on a unit n- pole placed at that point is called
Magnetic field intensity
Electric field intensity
Electromagnetic field intensity
Intensity magnetization
__________ is a substance of whose molecules consist of the same kind of atom.
Mixture
Compound
Element
Isotope
Another term for corona discharge.
Lightning
Sparking
Aurora
Corona Effect
The diameter of a hydrogen atom is approximately ______ cm.
1.1 x 10^-6
1.1 x 10^7
1.1 x 10^-8
1.1 x 10^-9
The electric flux density is a ________ quantity.
phasor
vector
scalar
variable
The tiniest element of matter
Atom
Proton
Electron
Neutron
States that the ratio of the thermal conductivity is proportional to the absolute temperature for all metals.
Wien's displacement law
Hartleys law
Hall's law
Wiedemann Franz law
One oersted (Oe) is equivalent to _____ Gb/cm.
What is the cgs unit of magnetomotive force?
Gilbert
Ampere- turn
Maxwell
Weber
The current of electric circuit is analogous to which quantity of a m
Mmf
Flux
Flux density
R eluctivity
Magnetic effects of the earth as a huge magnet with north and south poles.
Diamagnetic
Ferromagnetic
Terrestrial magnetism
Terrestrial ferromagnetism
The property of magnetic materials of retaining magnetism after withdrawal of the magnetizing force is known as
Retentivity
Reluctivity
Resistivity
Conductivity
Hydrogen is an example of a _____ material.
Paramagnetic
Diamagnetic
Ferromagnetic
N on- magnetic
A group of magnetically aligned atoms is called
Range
Lattice
Domain
Crystal
A law that states that the current in a thermionic diode varies directly with the three- halves power of anode voltage and inversely with the square of the distance between the electrodesa provided operating conditions are such that the current is limited only by the space charge.
Hall's law
Joule's law
Child's law
Coulomb's law
The lagging effect between flux density of the material and the magne
Permeance
Eddy current
Hysteresis
R eluctance
A law establishing the fact that the algebraic su of the rises and drops of the mmf around a closed loop of a magnetic circuit is equal to zero.
Kirchhoff's circuital law
Maxwell's circuital law
Ampere's circuital law
Coulomb's circuital law
If the solenoid is gripped by the right hand with the fingers pointing the direction of current flowa the outstretched thumb will then point the north pole. This is known as
Right hand rule
Helix rule
End rule
Cork screw rule
Materials whose permeabilities are slightly greater than that of free space
Paramagnetic
Non- magnetic
Ferromagnetic
Diamagnetic
What is the usual value of leakage coefficient for electrical machines?
0.5 to 1
1 to 5
5 to 10
1.15 to 1.25
Who discovered that a current-carrying conductor would move when placed in a magnetic field?
Michael Faraday
Andre Ampere
Hans Christian Oersted
Gustav Robert Kirchhoff
A law that states that the polarity of the induced voltage will oppose the change in magnetic flux causing the induction.
Joule's law
Faraday's law
Coulomb's law
Lenz' law
Which of the following is used by permanent magnets as the magnetic material?
iron
nickel
soft steel
hardened steel
A negative ion results when an atom gains an additional
Electron
Proton
Neutron
Atom
What is the measure of the density and sign of the electric charge at a point relative to that at some time?
Electric potential
Electric charge
Electric current
Electric intensity