CBSE
Multiple Choice QuestionsIf electron is moving from A to B in wire AB, then current induced in the coil is
anticlockwise
clockwise
arbitrary direction
no current will be induced
S.I unit of magnetic flux is :
tesla
oersted
weber
gauss
Two coils of self-inductance L1 and L2 are placed so close together that effective flux in one coil is completely linked with the other. If M is the mutual inductance between them, then
M = L1L2
M = L1/L2
M = L
ASsertion:- A larger dry cell has higher emf.
Reason:- The emf of a dry cell is proportional to its size.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false
Assertion: : A current continues to follow in superconducting coil even after switch is off.
Reason: Superconducting coils show Meissner effect.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false
Assertion: An emf is induced in a closed loop where magnetic flux is varied. The induced E is not a conservative field.
Reason: The line integral around the closed loop is non-zero.
If both assertion and reason are true and reason is the correct explanation of the assertion
If both assertion and reason are true but reason is not the correct explanation of the assertion
If assertion is true, but reason is false
Both assertion and reason are false statements
A 100 mH coil carries a current of 1 A. The energy stored in the magnetic field is
0.1 J
0.05 J
0.5 J
1 J
Assertion: We use a thick wire in the secondary of a step down transformer to reduce the production heat.
Reason: When the plane of the armature is parallel to the line of force of magnetic field, the magnitude of induced e.m.f. is maximum.
If both the assertion and reason are true and reason is a correct explanation of the assertion
If both assertion and reason are true but assertion is not a correct explanation of the assertion.
If the assertion is true but the reason is false.
If both assertion and reason are false
Figure shown is a distribution of charges. The flux of electric field due to these charges through the surface S is
zero
The mutual inductance of an induction coil is 5 H. In the primary coil, the current reduces from 5 A to zero is s What is the induced emf in the secondary coil?
2500 V
25000 V
2510 V
Zero
