The process by which an emf and hence current is generated or induced in a conductor when there is a change in the magnetic flux linking the conductor is called
Electromagnetic induction
Mutual induction
Faraday's law
Electromagnetic interference
Correct Answer :
A. Electromagnetic induction
Related Questions
The force of attraction or repulsion between two magnetic poles is inversely proportional to the square of the distance between them. This is known as
Newton's first law
Faraday's first law of electromagnetic induction
Coulomb's first law
Coulomb's second law
The tiniest element of matter
Atom
Proton
Electron
Neutron
An alloy of 22 percent iron and 78 per cent nickel.
Permalloy
Alnico
Constantan
M anganin
Hysteresis loss can be reduced by one of the following.
Increasing mmf of the circuit
Using material narrow hysteresis loop
Using ferromagnetic core
Laminating the magnetic circuit
______ is an electromagnet with its core in the form of a close magnetic ring.
S olenoid
Paraboloid
Toroid
Cycloid
A factor used to correct for the electrostatic forces of the more distant ions in an ionic solid.
Avogadro's number
Planck's constant
Boltzmann's constant
Madelung constant
The energy stored in an electrostatic field or electromagnetic field is called
Electromagnetic energy
Kinetic energy
Potential energy
R est energy
When the current flowsa the magnetic field ��. conductor is in what direction?
The same as the current direction
Opposite the current direction
Omnidirectional
In the direction determined by the left hand rule
The greater percentage of materials is _________.
diamagnetic
paramagnetic
ferromagnetic
non-magnetic
Residual magnetism refers to the flux densitya which exists in the iron core when the magnetic field intensity is
Minimized
Reduced to zero
Maximize
Unity
The conduction of electricity across the surface of a dielectric is called
creepage
skin effect
surface effect
crosstalk
A theorem which states that an electric current flowing in a circuit produces a magnetic field at external points equivalent to that due to a magnetic shell whose bounding edge is the conductor and whose strength of the current.
Joule's law
Faraday's law
Volta's theorem
Ampere's theorem
Theory of ferromagnetic phenomena which assumes each atom is a permanent magnet which can turn freely about its center under the influence of applied field and other magnets.
Ewing's theory of ferromagnetism
Oersted's ferromagnetism theory
Maxwell's magnetic theory
Ampere's circuital law
Which of the following is used by temporary magnets as the magnetic material?
Hardened steel
Cobalt steel
Soft iron
Tungsten steel
The reluctance of a magnetic circuit is not dependent on which of the following?
Number of turns of coil
Magnetomotive force
Flux density in the circuit
Current in the coil
Magnetic fields do not interact with
Moving permanent magnets
Stationary permanent magnets
Moving electric charges
Stationary electric charges
Hipernik is an alloy containing __________ iron and __________ nickel.
40% ; 60%
60% ; 40%
50% ; 50%
70% ; 30%
A commercial alloy of aluminum nickela and iron with cobalta copper and titanium added to produce about 12 grades.
Alnico
Brass
Aluminum
Constantan
The force between two charges placed a given distance apart ______ as the relative permittivity of the medium is increased.
increases
decreases
remains unchanged
becomes infinite
Calculate the permeability (in T/A. t/m) of a magnetic material that has a relative permeability of 300
3.78 x 10^4
3.78 x 10^-5
3.78 x 10^-3
3.78 x 10^-6
Permanent magnets can be found in
electric bells
earphones
relays
dy namic loudspeakers
Defined as a closed path in which magnetic induction or flux flows
Electric circuit
Magnetic circuit
Electronic circuit
Electromagnetic circuit
The contribution to the ionization in an ionization chamber by electrons liberated from t he walls.
Skin effect
Walt effect
Hall effect
Edison effect
The ratio of the permeability of material to the permiabiity of air or vacuum.
Relative permeability
Relative permittivity
Relative conductivity
Relative reluctivity
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
The unit of flux is _____ in cgs system.
Tesia
Gilbert
Maxwell
Oersted
The emission of electrons from hot bodies is called
Radiation effect
Edison effect
Skin effect
Half effect
An effect which is generally used in the gausameter to measure flux density.
Skin effect
Magnetic effect
Hall effect
Flywheel effect
The straight line passing through the two poles of magnet is called
Real axis
Cartesian axis
Magnetic axis
Imaginary axis
A magnetic circuit carries a flux iin the iron part and a fluxgin the air gap. What is the leakage coefficient?
i/g
i × g
g/ i
i + g