Free download in PDF CBSE Class 12 Physics MCQs & Answers. Here Gkseries provide Physics Solve Questions and Answers for CBSE Class 12 Students.
81
A paramagnetic sample shows a net magnetisation of 8 Am-1 when placed in an external magnetic field of 0.6 T at a temperature of 4K. When the same sample is placed in an external magnetic field of 0.2 T at a temperature of 16 K, the magnetisation will be [NCERT Exemplar]
88
The north pole of a long bar magnet was pushed slowly into a short solenoid connected to a short galvanometer. The magnet was held stationary for a few seconds with the north pole in the middle of the solenoid and then withdrawn rapidly. The maximum deflection of the galvanometer was observed when the magnet was
Answer: Lenz’s law is a consequence of the law of conservation of momentum..
95
There is a uniform magnetic field directed perpendicular and into the plane of the paper. An irregular shaped conducting loop is slowly changing into a circular loop in the plane of the paper. Then
A
current is induced in the loop in the anti-clockwise direction.
B
no current is induced in the loop.
C
ac is induced in the loop.
D
current is induced in the loop in the clockwise direction.
Answer: current is induced in the loop in the anti-clockwise direction.
96
The north pole of a bar magnet is rapidly introduced into a solenoid at one end (say A). Which of the following statements correctly depicts the phenomenon taking place?
A
No induced emf is developed.
B
The end A of the solenoid behaves like a south pole.
C
The end A of the solenoid behaves like north pole.
D
The end A of the solenoid acquires positive potential.
