How many electrons are needed in the valence orbit to give a material's stability?
Correct Answer :
A.
Related Questions
The idea of preventing one component from affecting another through their common electric and magnetic field is referred to as
Hall effect
Grounding
Shielding
Limiting
The ratio of the permeability of material to the permiabiity of air or vacuum.
Relative permeability
Relative permittivity
Relative conductivity
Relative reluctivity
The unit of flux is _____ in cgs system.
Tesia
Gilbert
Maxwell
Oersted
The dielectric constant of most materials lies between
1 and 10
10 and 20
20 and 50
50 and 100
A length of wire has a resistance of 10 ohms. What is the resistance of a wire of the same material three times as long and twice the cross-sectional area?
30 ohms
20 ohms
15 ohms
7 ohms
Which of the following magnetic materials can be easily magnetized in both direction?
Soft magnetic materials
Hard magnetic materials
High hysteresis loss materials
Low hysteresis loss materials
The current of electric circuit is analogous to which quantity of a m
Mmf
Flux
Flux density
R eluctivity
Used to maintain strength of magnetic field
Container
Air gap
Keeper
S ource
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
What is the SI unit of specific resistance or resistivity?
Ohm-circular mil per inch
Ohm-circular mil per foot
Ohm-m
Ohm-cm
Refers to the non- metallic materials that have the ferromagnetic properties of iron.
Ferrites
Ferromagnetic
Diamagnetic
Paramagnetic
The point in a magnet where the intensity of magnetic lines of force is maximum
Magnetic pole
South pole
North pole
Unit pole
Magnetic fields do not interact with
Moving permanent magnets
Stationary permanent magnets
Moving electric charges
Stationary electric charges
__________ is a substance of whose molecules consist of the same kind of atom.
Mixture
Compound
Element
Isotope
A good conductor has how many valence electrons?
Gases whose particles are charged are known as
Conductors
Insulators
Gaseous Conductors
Plasma
As the magnetic intensity decreasesa the relative permeability of a magnetic material
decreases
remains the same
increases
becomes zero
Another term for corona discharge.
Lightning
Sparking
Aurora
Corona Effect
Electric field intensity at a point is numerically equal to ________ at that point.
potential gradient
potential difference
dielectric constant
the force
The electrons in the last orbit of an atom are called _______ electrons.
free
valence
bound
thermionic
A law relating between the magnetic and electric susceptibilities and the absolute temperatures which is followed b ferromagnetsa antiferromagnetsa non-polar ferroelectricsa antiferroelectrics and some paramagnets.
Curie's Law
Child's Law
CR Law
Curie-Weiss Law
When a wire loop is rotated in a magnetic field the direction of the induced emf changes one in every _______ revolution
If you hold the conductor with right hand so that the stretched thumb points in the direction of the currenta then encircling fingers will give the direction of magnetic lines of force round the conductor. This is known as
Left hand cork screw rule
Right hand cork screw rule
Left hand rule
Right hand rule
Which of the following electric quantities is vector in character?
Field
Charge
Energy
Potential Difference
A negative ion results when an atom gains an additional
Electron
Proton
Neutron
Atom
One electron volt (1 eV) is equivalent to _____ joules
1.3 x 10^-19
1.4 x 10^-19
1.5 x 10^-19
1.6 x 10^-19
The magnetic flux of 2000 lines is how many Maxwells?
Materials that have very high permeabilities (hundreds and even thousands times of that of free space)
Paramagnetic
Non- magnetic
Ferromagnetic
Diamagnetic
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
Lenz' law states that the direction of the induced emf and hence current
Is determined by the rate of current flux
Is found by the right hand rule
Is found by the left hand rule
Always opposes the cause producing it