Which of the following has the least number of valence electrons?
Conductor
Semiconductor
Insulator
Semi- insulator
Correct Answer :
A. Conductor
Related Questions
Which of the following materials has the highest dielectric strength?
Glass
Oiled paper
Mica
Air
The magnetic field inside a solenoid
is zero
is uniform
increases with distance from the axis
decreases with distance from the axis
The force of attraction or repulsion between two magnetic poles is directly proportional to their strengths.
Newton's first law
Faraday's first law of electromagnetic induction
Coulomb's first law
Coulomb's second law
What is the maximum number of electrons that can be accommodated in the last orbit of an atom?
What revolves about the positive nucleus in a definite orbit?
Atom
Proton
Electron
Neutron
Used to maintain strength of magnetic field
Container
Air gap
Keeper
S ource
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
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 ratio of the permeability of material to the permiabiity of air or vacuum.
Relative permeability
Relative permittivity
Relative conductivity
Relative reluctivity
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 magnetic poles is _____ their poles strength.
equal to
directly proportional to
inversely proportional to
directly proportional to the square root of
__________ is a substance of whose molecules consist of the same kind of atom.
Mixture
Compound
Element
Isotope
The conduction of electricity across the surface of a dielectric is called
creepage
skin effect
surface effect
crosstalk
The ability of a material to conduct magnetic flux through it.
Permittivity
Reluctivity
Conductivity
Permeability
The electrons in the last orbit of an atom are called _______ electrons.
free
valence
bound
thermionic
Magnetic effects of the earth as a huge magnet with north and south poles.
Diamagnetic
Ferromagnetic
Terrestrial magnetism
Terrestrial ferromagnetism
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
If the number of valence electrons of an atom is less than 4a then the substance is probably
a metal
an insulator
a non-metal
a semiconductor
The current of electric circuit is analogous to which quantity of a m
Mmf
Flux
Flux density
R eluctivity
It is the reciprocal of reluctance and implies the case of readiness with which magnetic flux is developed.
R esistance
Conductance
Permeance
I nductance
When a wire loop is rotated in a magnetic field the direction of the induced emf changes one in every _______ revolution
The permittivity of a material is given by one of the following formulas.
DE
E/D
D^2/E
D/E
An atom or a group of atoms that carries a net electric charge.
Positive ion
Negative ion
Ion
Electron
The lagging effect between flux density of the material and the magne
Permeance
Eddy current
Hysteresis
R eluctance
Temporary magnets are commonly employed in
electric instruments
motors
moving coils loudspeakers
magnetos
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
One that has magnetic poles produced by internal atomic structure with no external current necessary
Diamagnetic
Permanent magnets
Paramagnetic
Electromagnetic
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
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 net electrical charge in an isolated system remains constant. This is known as
Law of conservation of charge
Coulomb's first law
Coulomb's second law
Law of conservation of energy