When the relative permeability of a material is much greater than 1a it is called _______ material.
diamagnetic
ferromagnetic
paramagnetic
non-magnetic
Correct Answer :
B. ferromagnetic
Related Questions
The electrons in the last orbit of an atom are called _______ electrons.
free
valence
bound
thermionic
The temperature coefficient of resistance of conductors is
positive
zero
negative
infinite
The temperature coefficient of resistance of a conductor ______ with an increase in temperature.
increases
decreases
remains the same
becomes negative
The dielectric constant of most materials lies between
1 and 10
10 and 20
20 and 50
50 and 100
Electronic current in a wire is the flow of ____________ electrons.
free
valence
bound
loose
The evaporation of electrons from a heated surface is called
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Convection
Thermionic emission
Conduction
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Watt
Kilowatt-hour
Kilowatt-second
Megawathour
A one cubic cm of copper has how many free electrons at room temperature?
80 × 10^18
8.5 × 10^22
20 × 10^10
50 × 10^20
All magnetic field originates from
moving electric charge
Iron atoms
Magnetic domain
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Defined as a closed path in which magnetic induction or flux flows
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Magnetic circuit
Electronic circuit
Electromagnetic circuit
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0.5 Tesia of flux density
5x 10^-5 Wb of flux
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i nfinite
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South
East
West
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Copper
Bismuth
Oxygen
Which of the following electric quantities is vector in character?
Field
Charge
Energy
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3.78 x 10^4
3.78 x 10^-5
3.78 x 10^-3
3.78 x 10^-6
The force between two magnetic poles is _______ their pole strengths.
directly proportional to
the sum of
inversely proportional to
the product of
If a 20 V potential is applied across a relay coil with 50 turns having 1 ? of resistancea the total magnetomotive producing magnetic flux in the circuit is
10 Wb
50 T
1000 A t/m
1000,t
What revolves about the positive nucleus in a definite orbit?
Atom
Proton
Electron
Neutron
One ampere- turn is equivalent to _____ gilberts
Magnetic effects of the earth as a huge magnet with north and south poles.
Diamagnetic
Ferromagnetic
Terrestrial magnetism
Terrestrial ferromagnetism
The force between two magnetic poles is _____ the relative permeability of the medium.
directly proportional to
independent of
inversely proportional to
equal to
What is the diameter of an atom?
About 10^-10 m
About 10^-10 cm
About 10^-10 mm
About 10^-10 �m
Which of the following materials has permeability slightly less than that of free space?
Paramagnetic
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Ferromagnetic
Diamagnetic
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scalar
phasor
vector
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This paper does not exhibit electricity because it contains the same number of
protons and electrons
neutrons and electrons
neutrons and positrons
atoms
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Number of turns of coil
Magnetomotive force
Flux density in the circuit
Current in the coil
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Mica
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Oiled paper