How does the magnetic compass needle behave in a magnetic field?
A. It assures a position right angle to magnetic field
B. It starts rotating
C. It assures a position which follows a line of magnetic flux
D. None of the above
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A certain amount of current flows through a ring shaped coil with fixed number of turns. How does the magnetic induction B varies inside the coil if an iron core is threaded into coil without dimensional change of coil?
A. Decreases
B. Increases
C. Remains same
D. First increases and then decreases depending on the depth of iron in¬sertion
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One telsa is equal to
A. 1 Wb/mm2
B. 1 Wb/m
C. 1 Wb/m2
D. 1 mWb/m2
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The susceptibility of paramagnetic materials generally lies between
A. 10-3 and 10-5
B. 10-3 and 10-7
C. 10-4 and 10-8
D. 10-2 and 10-5
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The materials are a bit inferior conductors of magnetic flux than air.
A. ferromagnetic
B. paramagnetic
C. diamagnetic
D. dielectric
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The use of permanent magnets is. not made in
A. magnetoes
B. energy meters
C. transformers
D. loud-speakers
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Degaussing is the process of
A. removal of magnetic impurities
B. removing gases from the materials
C. remagnetising metallic parts
D. demagnetising metallic parts
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Air gap has_______eluctance as compared to iron or steel path
A. little
B. lower
C. higher
D. zero
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Which of the following is a ferromagnetic material?
A. Tungsten
B. Aluminium
C. Copper
D. Nickel
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The two conductors of a transmission line carry equal current I in opposite directions. The force on each conductor is
A. proportional to 7
B. proportional to X
C. proportional to distance between the conductors
D. inversely proportional to I
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The ratio of intensity of magnetisation to the magnetisation force is known as
A. flux density
B. susceptibility
C. relative permeability
D. none of the above
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What is the magnitude and the direction of force per 1.1m length of a pair of conductors of a direct current linecarrying 10 amperes and spaced 100 mm apart
A. 22 x 10-8 N
B. 22 x 10-7 N
C. 22 x 10-6 N
D. 22 x 10-5 N
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The commonly used material for shielding or screening magnetism is
A. copper
B. aluminium
C. soft iron
D. brass
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Ferrites are materials.
A. paramagnetic
B. diamagnetic
C. ferromagnetic
D. none of the above
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The uniform magnetic field is
A. the field of a set of parallel conductors
B. the field of a single conductor
C. the field in which all lines of magnetic flux are parallel and equidistant
D. none of the above
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Core of an electromagnet should have
A. low coercivity
B. high susceptibility
C. both of the above
D. none of the above
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Fleming's left hand rule is used to find
A. Direction of magnetic field due to current carrying conductor
B. Direction of flux in a solenoid
C. Direction of force on a current carrying conductor in a magnetic field
D. Polarity of a magnetic pole
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Ferrites are a sub-group of
A. non-magnetic materials
B. ferro-magnetic materials
C. paramagnetic materials
D. ferri-magnetic materials
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The force between two long parallel conductors is inversely proportional to
A. Radius of conductors
B. Current in one conductor
C. Product of current in two conductors
D. Distance between the conductors
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Out of the following statements, concerning an electric field, which statement is not true?
A. The electric intensity is a vector quantity
B. The electric field intensity at a point is numerically equal to the force exerted upon a charge placed at that point
C. An electric field is defined as a point in space at which an electric charge would experience a force
D. Unit field intensity in the exertion of a force of one newton on a charge of one coulomb
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