Which of the following is a diamagnetic material?
Aluminum
Silver
Air
Cobalt
Correct Answer :
C. Air
Related Questions
The core of a magnetic equipment uses a magnetic material with
Least permeability
Low permeability
Moderate permeability
High permeability
The temperature coefficient of resistance of semiconductors is
positive
zero
negative
infinite
When the relative permeability of a material is much greater than 1a it is called _______ material.
diamagnetic
ferromagnetic
paramagnetic
non-magnetic
Which of the following is a natural magnet?
Steel
Magnesia
Lodestone
S oft iron
One electron volt (1 eV) is equivalent to _____ joules
1.3 x 10^-19
1.4 x 10^-19
1.5 x 10^-19
1.6 x 10^-19
The ability of a material to conduct magnetic flux through it.
Permittivity
Reluctivity
Conductivity
Permeability
The ratio of the total flux (flux in iron path) to the useful flux (flux in air gap)
Leakage flux
Leakage current
Leakage coefficient
Leakage factor
What is the SI unit of magnetic flux?
Tesla
Weber
Maxwell
Gauss
Who discovered superconductivity in 1911?
Kamerlingh Onnes
Alex Muller
GeoryBednorz
Charles Coulomb
Which of the following materials has the highest dielectric strength?
Glass
Oiled paper
Mica
Air
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
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
The tiniest element of matter
Atom
Proton
Electron
Neutron
The temperature coefficient of resistance of eureka is
p ositive
negative
almost zero
i nfinite
When a conductor is stationary and the magnetic field is moving or changing the emf induced is called
Statically induced emf
Mutually induced emf
Self induced emf
Dynamically induced emf
Electric field intensity at a point is numerically equal to ________ at that point.
potential gradient
potential difference
dielectric constant
the force
One coulomb of charge consists of ________ electrons.
624× 10^16
62.4 × 10^16
6.24 × 10^16
0.624 × 10^16
Defined as the flux density produced in it due to its own induced magnetism
Magnetic field intensity
Electric field intensity
Electromagnetic field intensity
Intensity magnetization
How many neutrons does a copper atom have?
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
The uncharged particles which have no effect on its atomic charge.
Nucleons
Electrons
Protons
Neutrons
Define as that pole which when placed in air from a similar and equal pole repels it with a force of newtons
North pole
South pole
Unit pole
Magnetic pole
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
The lagging effect between flux density of the material and the magne
Permeance
Eddy current
Hysteresis
R eluctance
If you hold the conductor with right hand so that the stretched thumb points in the direction of the currenta then encircling fingers will give the direction of magnetic lines of force round the conductor. This is known as
Left hand cork screw rule
Right hand cork screw rule
Left hand rule
Right hand rule
If the magnetic material is located within a coil through which alternating current (60 Hz frequency) flowsa then __________ hysteresis loops will be formed
A group of magnetically aligned atoms is called
Range
Lattice
Domain
Crystal
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 unit of reluctance?
Maxwell
Gauss
At/Wb
Weber
Which of the following is a vector quantity?
Magnetic potential
Magnetic field intensity
Magnetic permeability
F lux density