Materials that have very high permeabilities (hundreds and even thousands times of that of free space)
Paramagnetic
Non- magnetic
Ferromagnetic
Diamagnetic
Correct Answer :
C. Ferromagnetic
Related Questions
The total number of magnetic lines of force in a magnetic field is called
Magnetic flux
Magnetic flux density
Magnetic flux intensity
Magnetic potential
One that has magnetic poles produced by internal atomic structure with no external current necessary
Diamagnetic
Permanent magnets
Paramagnetic
Electromagnetic
An alloy of 40 percent iron and 60 percent nickel.
Alnico
Permalloy
Hipernik
Manganin
The permeability of a material having a flux density of 5 Wb/m^2 is 10^-5 H/m. What is the value of magnetizing force?
5 × 10^-5 N/Wb
500 × 10^3 N/Wb
4 × 10^7N/Wb
4 × 10^7N/Wb
One ampere- turn is equivalent to _____ gilberts
Under ordinary conditionsa a body is considered
positively charged
neutral
negatively charged
stable
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
What is the other name for dielectric strength?
Breakdown voltage
Electric intensity
Potential gradient
Dielectric constant
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
Which element has four valence electrons?
Conductor
Insulator
Semiconductor
Semi- insulator
Whenever a conductor cuts magnetic fluxa an emf is induced in it. This is known as
Coulomb's law
Joule's law
Faraday's law
Ohm's law
The resistance of a material is ____________ its area of cross-section.
directly proportional
independent of
inversely proportional to
equal to
How many neutrons does a copper atom have?
The core of a magnetic equipment uses a magnetic material with
Least permeability
Low permeability
Moderate permeability
High permeability
Which of the following materials has permeability slightly less than that of free space?
Paramagnetic
Non- magnetic
Ferromagnetic
Diamagnetic
The uncharged particles which have no effect on its atomic charge.
Nucleons
Electrons
Protons
Neutrons
Electronic current in a wire is the flow of ____________ electrons.
free
valence
bound
loose
The ratio of the permeability of material to the permiabiity of air or vacuum.
Relative permeability
Relative permittivity
Relative conductivity
Relative reluctivity
Used to maintain strength of magnetic field
Container
Air gap
Keeper
S ource
Electron is a Greek word for
amber
Fire
Stone
Heat
Why is it that the magnitude of magnetomotive force required for air gap is much greater than that required for iron part of a magnetic circuit?
Because air is a gas
Because air has the highest relative permeability
Because air is a conductor of magnetic flux
Because air has the lowest relative permeability
The greater percentage of materials is _________.
diamagnetic
paramagnetic
ferromagnetic
non-magnetic
A magnetic material losses its ferromagnetic properties at a point called
Curie temperature
Inferred absolute temperature
Room temperature
Absolute temperature
Who demonstrated that there are magnetic effects around every current-carrying conductor and that current-carrying conductors can attract and repel each other just like magnets?
Luigi Galvani
Hans Christian Oersted
Charles Coulomb
Andre Ampere
The magnetic potential in a magnetic circuit can be measured in terms of
Mmf
Emf
Farad
Coulomb
The phenomenon by which a magnetic substance becomes a magnet when it is place near a magnet
Magnetic effect
Magnetic phenomenon
Magnetic induction
Electromagnetic induction
All magnetic field originates from
moving electric charge
Iron atoms
Magnetic domain
Permanent magnets
When a wire loop is rotated in a magnetic field the direction of the induced emf changes one in every _______ revolution
If two similar charges 1 coulomb each are placed 1 m apart in aira then the force of repulsion is
8 × 10^6 N
9 × 10 ^9 N
10^6 N
5 × 10^6 N
A magnetizing force of 1000 AT/m will produce a flux density of __________ i
1.257 mWb/m^2
0.63 Wb/m^2
1.257 Wb/m^2
0.63 mWb/m^2