Multiple Choice QuestionsA bar magnet is allowed to fall vertically through a copper coil placed in a horizontal plane. The magnet falls with a net acceleration, is
Zero
= g
< g
> g
Which of the following properties is 'False' for a bar magnet ?
It doesn't produce magnetic field.
Its like poles repel and unlike poles attract.
Its poles cannot be separated
It points in North-South direction when suspended.
A jet plane of wing span 20 m is travelling towards west at a speed of 400 ms-1. If the earth's total magnetic field is 4 × 10-4 T and the dip angle is 30°, at that place, then the voltage differences developed across the ends of the wing is
0.8 V
6.4 V
3.2 V
1.6 V
A magnet is dropped down an infinitely long vertical copper tube. Then
the magnet moves with continuously decreasing velocity and ultimately comes to rest.
the magnet moves with continuosly increasing velocity and ultimately acquires a constant terminal velocity.
the magnet moves with continuously increasing velocity and acceleration.
the magnet moves with continuosly increasing velocity but constant acceleration.
The variation of the intensity of magnetisation (I) with respect to the magnetising field (H) in a diamagnetic substance is described by the graph
OC
OD
OA
OB
The magnetic susceptibility is negative for,
a paramagnetic material only
ferromagnetic material only
paramagnetic and ferromagnetic materials
paramagnetic and ferromagnetic materials
A wire carrying current I has the shape as shown in the adjoining figure. Linear parts of the wire are very long and parallel to X -axis while semicircular portion of radius R is lying in a Y-Z plane. The magnetic field at point O is.
A compass needle which is allowed to move in a horizontal plane is taken to a geomagnetic pole. it
will become rigid showing no movement
will stay in any position
will stay in the north-south direction only
will stay in the north-south direction only
