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
Correct Answer :
D. 0.1 Wb/m^2
Related Questions
If the distance between two magnetic poles decreases by 2 timesa the force between them
decreases two times
increases four times
increases two times
decreases four times
The resistivity of a conductor ___________ with an increase in temperature.
increases
decreases
remains the same
becomes zero
Defined as the number of lines per unit area through any substance in a plane at right angles to the lines of force
Flux
Flux lines
Flux density
Flux intensity
The straight line passing through the two poles of magnet is called
Real axis
Cartesian axis
Magnetic axis
Imaginary axis
One weber of flux is equal to _______ magnetic lines of force.
10^6
10^10
4 × 10^7
10^8
What is the practical unit of electrical energy?
Watt
Kilowatt-hour
Kilowatt-second
Megawathour
An effect which is generally used in the gausameter to measure flux density.
Skin effect
Magnetic effect
Hall effect
Flywheel effect
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1.257 mWb/m^2
0.63 Wb/m^2
1.257 Wb/m^2
0.63 mWb/m^2
The evaporation of electrons from a heated surface is called
Radiation
Convection
Thermionic emission
Conduction
Which of the following materials has the highest dielectric strength?
Glass
Oiled paper
Mica
Air
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increases
decreases
remains unchanged
becomes infinite
A factor used to correct for the electrostatic forces of the more distant ions in an ionic solid.
Avogadro's number
Planck's constant
Boltzmann's constant
Madelung constant
What is the unit of magnetomotive force?
Volt
Tesla
Ampere- turn
Weber
The net electrical charge in an isolated system remains constant. This is known as
Law of conservation of charge
Coulomb's first law
Coulomb's second law
Law of conservation of energy
What is the SI unit of conductance?
Siemens
Mhos
Ohms
1/Ohms
The space outside the magnet where its pole have a force of attraction or repulsion on a magnetic pole is called
Magnetic field
Electric field
Electromagnetic field
Free Space Field
Which of the following has the highest permeability?
Soft iron
Steel
Air
Permalloy
If the value of 25 a conductor is 1/255 per oCa then the value of 20is
1/300 per oC
1/250 peroC
1/230 per oC
1/260 per oC
A positively charged body has
deficit of electrons
excess of neutrons
excess of electrons
deficit of protons
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
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 emf induced in a coil due to the change of its own flux linked with it is called
Mutually induced emf
Dynamically induced emf
Statically induced emf
Self induced emf
What determines the atomic number of an element?
The number of protons
The number of electrons
The number of neutrons
The number of neutrons and protons
The electrons in the last orbit of an atom are called _______ electrons.
free
valence
bound
thermionic
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
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Curie's Law
Child's Law
CR Law
Curie-Weiss Law
There are how many compounds available in nature?
300a000
Unlimited
A 6- V battery is connected across a solenoid of 100 turns having a resistance of 2 ?a Calculate the number of ampere turns?
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deficit of electrons
excess of protons
excess of electrons
deficit of neutrons
What is the SI unit of reluctance?
At
At/m
N/Wb
At/Wb