Q.1
The rate of rise of current through an inductive coil is maximum
Q.2
The property of a material which opposes the creation of magnetic flux in it is known as
Q.3
Conductivity is analogous to
Q.4
The relative permeability of a ferromagnetic material is
Q.5
Energy stored by a coil is doubled when its current is increased by percent.
Q.6
Hard steel is suitable for making permanent magnets because
Q.7
The unit of reluctance is
Q.8
Hysteresis loss least depends on
Q.9
When both the inductance and resistance of a coil are doubled the value of
Q.10
Silicon steel is used in electrical machines because it has
Q.11
A ferrite core has less eddy current loss than an iron core because
Q.12
Conductance is analogous to
Q.13
Those magnetic materials are best suited for making armature and transformer cores which have ________permeability and _________hysteresis loss.
Q.14
The initial rate of rise of current through a coil of inductance 10 H when suddenly connected to a D.C. supply of 200 V is ___________Vs
Q.15
If the area of hysteresis loop of a material is large, the hysteresis loss in this material will be
Q.16
The unit of retentivity is
Q.17
An air gap is usually inserted in magnetic circuits to
Q.18
Permanent magnets are normally made of
Q.19
A material for good magnetic memory should have
Q.20
Reciprocal of reluctance is
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