Hysteresis is a phenomenon of _________ in a magnetic circuit.
setting up constant flux
lagging of H behind B
lagging B behind H
leading B ahead H
Correct Answer :
C. lagging B behind H
Related Questions
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
Hysteresis refers to the ______ between flux density of the material and the magnetizing force applied.
Leading effect
Ratio
Equality
Lagging effect
Who developed the electromagnetic theory of light in 1862?
Heinrich Rudolf Hertz
Wilhelm Rontgen
James Clerk Maxwell
Andre Ampere
Formed when there exist distant electronic interactions between (opposite) charges present in the neighboring atoms or molecules.
Ionic bond
Covalent bond
Metallic bond
Van der Waals bond
The B-H curve for ________ is a straight line passing through the origin.
cobalt
air
hardened steel
soft iron
The property of magnetic materials of retaining magnetism after withdrawal of the magnetizing force is known as
Retentivity
Reluctivity
Resistivity
Conductivity
The magnetic flux of 2000 lines is how many Maxwells?
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 contribution to the ionization in an ionization chamber by electrons liberated from t he walls.
Skin effect
Walt effect
Hall effect
Edison effect
What is the measure of the density and sign of the electric charge at a point relative to that at some time?
Electric potential
Electric charge
Electric current
Electric intensity
Electric field intensity at a point is numerically equal to ________ at that point.
potential gradient
potential difference
dielectric constant
the force
Ohm's law cannot be applied to which material?
Copper
Silver
Silicon carbide
Aluminum
Another term for corona discharge.
Lightning
Sparking
Aurora
Corona Effect
The current of electric circuit is analogous to which quantity of a m
Mmf
Flux
Flux density
R eluctivity
The magnitude of the induced emf in a coil is directly proportional to the rate of change of flux linkages. This is known as
Joule's Law
Faraday's second law of electromagnetic induction
Faraday's first law of electromagnetic induction
Coulomb's Law
An atom or a group of atoms that carries a net electric charge.
Positive ion
Negative ion
Ion
Electron
Which of the following is a diamagnetic material?
Aluminum
Silver
Air
Cobalt
Defined as a closed path in which magnetic induction or flux flows
Electric circuit
Magnetic circuit
Electronic circuit
Electromagnetic circuit
If the resistance of a material 2 m long and 2 m^2 in area of cross-section is 1.6 ×10^-8 ?a then its resistivity is
3.2 × 10^-8 ?-m
1.6 × 10^-8 ?-m
0.64 × 10^-8 ?-m
0.16 × 10^-8 ?-m
When a current carrying conductor is placed in a magnetic fielda the maximum force will act on the conductor when the conductor is at an angle of _______ to the magnetic field.
45o
60o
30o
90o
If the length and area of cross-section of a wire are doubleda then its resistance
becomes four times
becomes sixteen times
remains the same
becomes two times
Magnetic intensity is a
Phasor quantity
Physical quantity
Scalar quantity
Vector quantity
The magnetic field around the conductor is determined by the
Size of the conductor
Amount of current
Current divided by the resistance
Resistance divided by the current
The K shell or the first shell has how many permissible number of orbiting electrons?
All magnetic field originates from
moving electric charge
Iron atoms
Magnetic domain
Permanent magnets
Under ordinary conditionsa a body is considered
positively charged
neutral
negatively charged
stable
The mass of proton is __________ the mass of an electron.
equal to
about 1837 times
less than
200 tim es
Electric potential is a _______ quantity.
scalar
phasor
vector
variable
______ is an electromagnet with its core in the form of a close magnetic ring.
S olenoid
Paraboloid
Toroid
Cycloid
The relation between absolute permittivity of air ( 0)a absolute p and velocity of light (c) is given by
0 0= c^2
0 0= c
1/ 0 0= c
1/ 0 0= c^2