What is the other name for dielectric strength?
Breakdown voltage
Electric intensity
Potential gradient
Dielectric constant
Correct Answer :
A. Breakdown voltage
Related Questions
When the relative permeability of a material is slightly less than 1a it is called _____ material.
diamagnetic
ferromagnetic
paramagnetic
non-magnetic
The ratio of the permeability of material to the permiabiity of air or vacuum.
Relative permeability
Relative permittivity
Relative conductivity
Relative reluctivity
If the value of 25 of a conductor is 1/230 per oCa then the value of 0is
1/180 peroC
1/150 per oC
1/280 per oC
1/230 per oC
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
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 permeability of permalloy is
Very much greater than permeability of air
Slightly greater than permeability of air
Slightly less than permeability of air
Equal to the permeability of air
Materials that have very high permeabilities (hundreds and even thousands times of that of free space)
Paramagnetic
Non- magnetic
Ferromagnetic
Diamagnetic
The uncharged particles which have no effect on its atomic charge.
Nucleons
Electrons
Protons
Neutrons
One coulomb of charge consists of ________ electrons.
624× 10^16
62.4 × 10^16
6.24 × 10^16
0.624 × 10^16
The force between two magnetic poles is _______ their pole strengths.
directly proportional to
the sum of
inversely proportional to
the product of
The emission of electrons from hot bodies is called
Radiation effect
Edison effect
Skin effect
Half effect
Germanium atom has ______ protons and ______ electrons.
32, 32
32, 42
42, 32
34, 34
If the number of valence electrons of an atom is less than 4a the substance is called
a conductor
a semiconductor
an insulator
a superconductor
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
The electrons in the last orbit of an atom are called _______ electrons.
free
valence
bound
thermionic
Electric field intensity at a point due to a given charge ______ if the relative permittivity of the medium decreases.
decreases
remains unchanged
increases
b ecomes zero
If the number of valence electrons of an atom is more than 4a the substance is called
a semiconductor
a conductor
an insulator
a semi-insulator
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
Used to maintain strength of magnetic field
Container
Air gap
Keeper
S ource
A 6- V battery is connected across a solenoid of 100 turns having a resistance of 2 ?a Calculate the number of ampere turns?
If the value of 0 a conductor is 1/234 per oCa then the value of 18is
1/218 per oC
1/252 peroC
1/272 per oC
1/273 per oC
In electro-mechanical conversion devices like generators and motors the reason why a small air gap is left between the rotor and stator is to
permit mechanical clearance
increase flux density in air gap
decrease the reluctance of magnetic path
complete the magnetic path
One oersted (Oe) is equivalent to _____ Gb/cm.
Which of the following electric quantities is vector in character?
Field
Charge
Energy
Potential Difference
What solid has no defined crystal structure except perhaps in the arrangement of the nearest neighboring atoms or ions?
Crystalline
Amorphous
Polycrystalline
Poly amorphous
The phenomenon that when an electric current passes through an anisotropic crystala there is an absorption or liberation of heat due to the non-uniformity in current distribution.
Bridgman effect
Corona effect
Dember effect
Destriau effect
This paper does not exhibit electricity because it contains the same number of
protons and electrons
neutrons and electrons
neutrons and positrons
atoms
Which of the following materials has the highest dielectric strength?
Glass
Oiled paper
Mica
Air
All magnetic field originates from
moving electric charge
Iron atoms
Magnetic domain
Permanent magnets
Electric field intensity at a point is numerically equal to ________ at that point.
potential gradient
potential difference
dielectric constant
the force