Hipernik is an alloy containing __________ iron and __________ nickel.
40% ; 60%
60% ; 40%
50% ; 50%
70% ; 30%
Correct Answer :
A. 40% ; 60%
Related Questions
The ratio between the intensity of magnetization produced in a substance to the magnetizing force producing it
Magnetic Reluctivity
Magnetic Resistivity
Magnetic susceptibility
Magnetic conductivity
The ability of a material to conduct magnetic flux through it.
Permittivity
Reluctivity
Conductivity
Permeability
What is the value of the absolute permittivity of air?
8.854 F/m
8.854 × 10^-12 mF/m
8.854× 10^-12 F/m
8.854 × 10^-12 F/m
Electric lines of force leave or enter the charge surface at an angle of
30o
45 o
90o
depending upon the angle of launch and entry
A good conductor has how many valence electrons?
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
The flux density in an air-cored coil is 10^-3 Wb/m^2. With a cast iron core of relative permeability 100 inserteda the flux density will become
10^-3 Wb/m^2
10^-2 Wb/m^2
10^3 Wb/m^2
0.1 Wb/m^2
The magnetic flux of 2000 lines is how many Maxwells?
Magnetic intensity is a
Phasor quantity
Physical quantity
Scalar quantity
Vector quantity
Who discovered superconductivity in 1911?
Kamerlingh Onnes
Alex Muller
GeoryBednorz
Charles Coulomb
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 diameter of a hydrogen atom is approximately ______ cm.
1.1 x 10^-6
1.1 x 10^7
1.1 x 10^-8
1.1 x 10^-9
The force between two magnetic poles is _____ their poles strength.
equal to
directly proportional to
inversely proportional to
directly proportional to the square root of
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
Amorphous solid is also called
Crystalline
Non- crystalline
Polycrystalline
Homogenous
The current of electric circuit is analogous to which quantity of a m
Mmf
Flux
Flux density
R eluctivity
The resistance of a material is ____________ its area of cross-section.
directly proportional
independent of
inversely proportional to
equal to
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 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
What determines the value of the temperature coefficient of resistance of a material?
length
cross-sectional area
volume
nature and temperature
The permittivity of a material is given by one of the following formulas.
DE
E/D
D^2/E
D/E
How many turns are needed to produce a magnetomotive force of 1000 A.t for a coil with 6 amperes?
6000 turns
600 turns
167 turns
67turns
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
Calculate the permeability (in T/A. t/m) of a magnetic material that has a relative permeability of 300
3.78 x 10^4
3.78 x 10^-5
3.78 x 10^-3
3.78 x 10^-6
Electron is a Greek word for
amber
Fire
Stone
Heat
Magnetic field intensity is a ________ quantity.
scalar
phasor
vector
variable
Who discovereda the relationship between magnetism and electricity that serves as the foundation for the theory of electromagnetism?
Luigi Galvani
Hans Christian Oersted
Andre Ampere
Charles Coulomb
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
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
Refers to the non- metallic materials that have the ferromagnetic properties of iron.
Ferrites
Ferromagnetic
Diamagnetic
Paramagnetic