Refers to the magnetic lines
Flux
Hysteresis
Current
Magnetomotive force
Correct Answer :
A. Flux
Related Questions
The contribution to the ionization in an ionization chamber by electrons liberated from t he walls.
Skin effect
Walt effect
Hall effect
Edison effect
The magnetic energy stored in an inductor is ______ current.
Directly proportional to
Inversely proportional to
Directly proportional to the square of
Inversely proportional to the square of
A magnetic field is
The current flow through space around a permanent magnet
The force set up when current flows through a conductor
The force that drives current through a resistor
The force between the plates of a charged capacitor
When a wire loop is rotated in a magnetic field the direction of the induced emf changes one in every _______ revolution
What is the main advantage of temporary magnets?
The magnetic flux can be changed.
Hysteresis can be decreased.
Magnetic materials can be used.
Abundance of ferromagnetic material that can be temporarily magnetized.
There are how many compounds available in nature?
300a000
Unlimited
A substance that attracts pieces iron
Conductor
Semiconductor
Magnet
All of the above
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
Hysteresis loss can be reduced by one of the following.
Increasing mmf of the circuit
Using material narrow hysteresis loop
Using ferromagnetic core
Laminating the magnetic circuit
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
What is the cgs unit of magnetomotive force?
Gilbert
Ampere- turn
Maxwell
Weber
The greater percentage of materials is _________.
diamagnetic
paramagnetic
ferromagnetic
non-magnetic
Electric field intensity is a ________.
scalar
phasor
vector
variable
The force of attraction or repulsion between two magnetic poles is directly proportional to their strengths.
Newton's first law
Faraday's first law of electromagnetic induction
Coulomb's first law
Coulomb's second law
Two similar polesa each 1Wba placed 1 m apart in air will experience a repulsive force of
63000 N
63 × 10^-3 N
8 × 10^12 N
796 kN
One of the common application of an air- cored choke.
Radio frequency
Audio frequency
Power supply
Power transformer
What is the relative permittivity of air?
8.854 × 10^-12
4 × 10^7
How many neutrons does a copper atom have?
A length of wire has a resistance of 10 ohms. What is the resistance of a wire of the same material three times as long and twice the cross-sectional area?
30 ohms
20 ohms
15 ohms
7 ohms
If the number of valence electrons of an atom is less than 4a then the substance is probably
a metal
an insulator
a non-metal
a semiconductor
The core of a magnetic equipment uses a magnetic material with
Least permeability
Low permeability
Moderate permeability
High permeability
The induced emf in a wire loop that is moved parallel to a uniform magnetic field is
Zero
Dependent on the area of the loop
Dependent on the shape of the loop
Dependent on the magnitude of the field
A principle that states that only two electrons with different spins are allowed to exist in a given orbit
Bohr's principle
Pauli exclusion principle
Avogadro's principle
Coulomb's principle
Who discovered superconductivity in 1911?
Kamerlingh Onnes
Alex Muller
GeoryBednorz
Charles Coulomb
The conduction of electricity across the surface of a dielectric is called
creepage
skin effect
surface effect
crosstalk
When the relative permeability of a material is slightly more than 1a it is called ______ material.
diamagnetic
ferromagnetic
paramagnetic
non-magnetic
The amount of magnetizing force to counter balance the resid magnetic material is referred to as
Reluctivity
Susceptivity
Coercivity
Retentivity
A magnetic circuit carries a flux iin the iron part and a fluxgin the air gap. What is the leakage coefficient?
i/g
i × g
g/ i
i + g
The permeability of a material having a flux density of 5 Wb/m^2 is 10^-5 H/m. What is the value of magnetizing force?
5 × 10^-5 N/Wb
500 × 10^3 N/Wb
4 × 10^7N/Wb
4 × 10^7N/Wb
Refers to the non- metallic materials that have the ferromagnetic properties of iron.
Ferrites
Ferromagnetic
Diamagnetic
Paramagnetic