The branch of Engineering which deals with the magnetic effect of electric current is known as
Magnetism
Electromagnetism
Electrical engineering
Electronics engineering
Correct Answer :
B. Electromagnetism
Related Questions
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 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
The energy stored in an electrostatic field or electromagnetic field is called
Electromagnetic energy
Kinetic energy
Potential energy
R est energy
A permanent magnet does not exert a force on
an unmagnetized iron bar
a magnetized iron bar
a moving electric charge
a stationary electric charge
Electronic current in a wire is the flow of ____________ electrons.
free
valence
bound
loose
Electrons at the outer shell are called
Outer shell electrons
Inner shell electrons
Semiconductor electrons
Valence electrons
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
The magnetic materials should have a large hysteresis loss for one of the following applications.
Transformers
ACmotors
Permanent Magnets
DC generators
An alloy of 22 percent iron and 78 per cent nickel.
Permalloy
Alnico
Constantan
M anganin
Germanium atom has ______ protons and ______ electrons.
32, 32
32, 42
42, 32
34, 34
What is the reluctance of a magnetic path having a length of 2x 10^-3m and crosssectional area of 2.5 x 10^-3 m^2?
6366 A, t/Wb
6000 A, t/Wb
8x10^-3 A, t/Wb
0.8 A, t/Wb
What is the cgs unit of magnetomotive force?
Gilbert
Ampere- turn
Maxwell
Weber
Electric field intensity at a point is numerically equal to ________ at that point.
potential gradient
potential difference
dielectric constant
the force
What is used as the dielectric material in high voltage transformers?
Mica
Paraffin
Porcelain
Oiled paper
Residual magnetism refers to the flux densitya which exists in the iron core when the magnetic field intensity is
Minimized
Reduced to zero
Maximize
Unity
What is the relative permittivity of air?
8.854 × 10^-12
4 × 10^7
The quantity 10^6 maxwells is equivalent to one
Weber
Gauss
Gilbert
Tesla
If on looking at any one end of a solenoid; the direction of current flow is found to be clockwise then the end under observation is a south pole. This is known as
Right hand rule
Left hand rule
Cork screw rule
End Rule
Permeance of a magnetic circuit is _________ the cross-sectional area of the circuit.
directly proportional to
inversely proportional to
dependent of
independent of
The electric potential at a point in air due to a charge is 21 V. If the air is replaced by a medium of relative permittivity of 3a then electric potential at that point will be
63 V
21 V
7 V
42 V
The B-H curve of ________ is not a straight line.
air
wood
silicon steel
soft iron
The dielectric constant of most materials lies between
1 and 10
10 and 20
20 and 50
50 and 100
Three charges of +5 Ca -6 C and +9 C are placed inside a sphere. What is the total flux passing through the surface of sphere?
8 C
14 C
20 C
-6 C
The magnetic field inside a solenoid
is zero
is uniform
increases with distance from the axis
decreases with distance from the axis
The current of electric circuit is analogous to which quantity of a m
Mmf
Flux
Flux density
R eluctivity
The greater percentage of materials is _________.
diamagnetic
paramagnetic
ferromagnetic
non-magnetic
The relative permeability of a magnetic material is 10^5. What is its permeability?
4 × 10^5 H/m
4 × 10^-12 H/m
4× 10^-2 H/m
4 × 10^7H/m
If the number of valence electrons of an atom is exactly 4a then the substance is called
a semiconductor
a conductor
an insulator
a cryogenic conductor
Hysteresis refers to the ______ between flux density of the material and the magnetizing force applied.
Leading effect
Ratio
Equality
Lagging effect
At/m is a unit of
mmf
magnetic force
reluctance
magnetic flux density