If a magnetic flux cuts across 200 turns at a rate of 2Wb/sa the induced voltage according to Faraday's law is about
400 V
100 V
200 V
600 V
Correct Answer :
A. 400 V
Related Questions
One weber of flux is equal to _______ magnetic lines of force.
10^6
10^10
4 × 10^7
10^8
Permeance of a magnetic circuit is _________ the cross-sectional area of the circuit.
directly proportional to
inversely proportional to
dependent of
independent of
What is the relative permittivity of air?
8.854 × 10^-12
4 × 10^7
Hipernik is an alloy containing __________ iron and __________ nickel.
40% ; 60%
60% ; 40%
50% ; 50%
70% ; 30%
The magnetic flux through a wire loop in a magnetic field does not d
T he area of the loop
The magnitude of the field
The shape of the loop
The angle between the plane of the loop and the direction
This paper does not exhibit electricity because it contains the same number of
protons and electrons
neutrons and electrons
neutrons and positrons
atoms
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
When a current carrying conductor is placed in a magnetic fielda the maximum force will act on the conductor when the conductor is at an angle of _______ to the magnetic field.
45o
60o
30o
90o
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
Ohm's law cannot be applied to which material?
Copper
Silver
Silicon carbide
Aluminum
Which of the following is used by temporary magnets as the magnetic material?
Hardened steel
Cobalt steel
Soft iron
Tungsten steel
A law establishing the fact that the algebraic su of the rises and drops of the mmf around a closed loop of a magnetic circuit is equal to zero.
Kirchhoff's circuital law
Maxwell's circuital law
Ampere's circuital law
Coulomb's circuital law
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
Which of the following materials has the highest dielectric strength?
Glass
Oiled paper
Mica
Air
The force acting on a pole of 5 Wb is 25 N. What is the intensity of the magnetic field?
5 N/Wb
25 N/Wb
125 N/Wb
0.2 N/Wb
The hot resistance of an incandescent lamp is about _______ its cold resistance.
10 times
100 times
5 times
50 times
A good conductor has how many valence electrons?
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
Electric field intensity at a point is numerically equal to ________ at that point.
potential gradient
potential difference
dielectric constant
the force
Ohm's law can be used only to a _____ circuit or component.
Unilateral
Exponential
Trivalent
Linear
An atom or a group of atoms that carries a net electric charge.
Positive ion
Negative ion
Ion
Electron
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
If the relative permittivity of a material is 10a then its permittivity is
4 × 10^7F/m
4 × 10^-6 F/m
8.854× 10^-11 F/m
8.854 × 10^-12 F/m
Lenz's law is the consequence of the law of conservation of
Energy
Charge
Field lines
Momentum
Why is it that the magnitude of magnetomotive force required for air gap is much greater than that required for iron part of a magnetic circuit?
Because air is a gas
Because air has the highest relative permeability
Because air is a conductor of magnetic flux
Because air has the lowest relative permeability
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
Which of the following is a natural magnet?
Steel
Magnesia
Lodestone
S oft iron
Electric field intensity is a ________.
scalar
phasor
vector
variable
The ability of a mechanically stressed ferromagnetic wire to recognize rapid switching of magnetization when subjected to a dc magnetic field.
Wartheim effect
Wiedemann effect
Wiegand effect
Edison effect
The mass of proton is __________ the mass of an electron.
equal to
about 1837 times
less than
200 tim es