What is the SI unit of magnetic flux?
Tesla
Weber
Maxwell
Gauss
Correct Answer :
B. Weber
Related Questions
When the relative permeability of a material is much greater than 1a it is called _______ material.
diamagnetic
ferromagnetic
paramagnetic
non-magnetic
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
The core of a transformer heats up when its primary is fed from an ac source because of
permeability
ferromagnetism
reluctance of core
hysteresis loss
What is the SI unit of specific resistance or resistivity?
Ohm-circular mil per inch
Ohm-circular mil per foot
Ohm-m
Ohm-cm
The unit of electrical energy is
Joule
Watt- second
Kilowatt hour
All of these
Flux linkages equals
Flux times area of core
Flux times number of turns times area of core
Flux times number of turns times length of core
Flux times number of turns
The ratio of the permeability of material to the permiabiity of air or vacuum.
Relative permeability
Relative permittivity
Relative conductivity
Relative reluctivity
Hipernik is an alloy containing __________ iron and __________ nickel.
40% ; 60%
60% ; 40%
50% ; 50%
70% ; 30%
Refers to the non- metallic materials that have the ferromagnetic properties of iron.
Ferrites
Ferromagnetic
Diamagnetic
Paramagnetic
The magnetic field of a bar magnet most closely resembles the magnetic field of
a horseshoe magnet
a straight current- carrying wire
a stream of electrons moving parallel to one another
a current- carrying wire loop
One farad equals
1 coulomb/volt
1 newton/coulomb
1 newton-meter
1 volt/second/ampere
The unit of flux density is
Wb/m
Tesla
At/m
N/Wb
The mass of proton is __________ the mass of an electron.
equal to
about 1837 times
less than
200 tim es
Electric field intensity is a ________.
scalar
phasor
vector
variable
The amount of magnetizing force to counter balance the resid magnetic material is referred to as
Reluctivity
Susceptivity
Coercivity
Retentivity
The magnetic field of a magnetized iron bar when strongly heated
Becomes weaker
Becomes stronger
Reverses in direction
is unchanged
Permanent magnets can be found in
electric bells
earphones
relays
dy namic loudspeakers
Defined as a closed path in which magnetic induction or flux flows
Electric circuit
Magnetic circuit
Electronic circuit
Electromagnetic circuit
The energy stored in an electrostatic field or electromagnetic field is called
Electromagnetic energy
Kinetic energy
Potential energy
R est energy
A 200-watt lamp working for 24 hours will consume approximately _____ units.
Magnetic field intensity is a ________ quantity.
scalar
phasor
vector
variable
The direction of force o a current carrying conductor placed in a m found by
Cork screw rule
Fleming's left hand rule
Fleming's right hand rule
using a compass
One of the solid structures in which the position of the atoms or ions are predetermined
Crystalline solid
Amorphous solid
Polycrystalline solid
Poly amorphous solid
An alloy of 40 percent iron and 60 percent nickel.
Alnico
Permalloy
Hipernik
Manganin
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
Steel is hard to magnetize because of its
Low permeability
High permeability
High density
High retentivity
Electron is a Greek word for
amber
Fire
Stone
Heat
Who developed the electromagnetic theory of light in 1862?
Heinrich Rudolf Hertz
Wilhelm Rontgen
James Clerk Maxwell
Andre Ampere
What is the maximum number of electrons that can be accommodated in the last orbit of an atom?
The reluctance of the magnetic circuit is ________ relative permeability of the material comprising the circuit.
directly proportional to
inversely proportional to
independent of
dependent of