Q.1
The time period of a freely suspended magnet does not depend upon
  • a) length of magnet
  • b) the pole strength of the magnet
  • c)the horizontal component of magnetic field of the earth
  • d)the length of the suspension
Q.2
On the application of appropriate steady magnetic field, a high speed electron travelling horizontally through vacuum may be given a net initial acceleration
  • a) in any direction
  • b) only upward, downward or side ways
  • c)only forward or backwards
  • d)in any direction except forward or backwards
Q.3
For paramagnetic material, the dependence of the magnetic susceptibility X on the absolute temperature T is given by [raj. PMT 11996]
  • a) X ∝ T
  • b) X ∝ constant ×T
  • c) X ∝ (1/T)
  • d) X=constant
Q.4
The magnetic induction and the magnetic field inside the iron core of an electromagnet is 1.07 weber per metre2 and 150 ampere per metre. then the relative permeability of this iron is
  • a)1.07/150
  • b) 10-7/4π
  • d)1.07 × 10+7 / 150 × 4π
  • c)1.07 × 10⁻⁷ / 150 × 4π
Q.5
The time period of freely suspended magnet does not depend upon
  • a) length of the magnet
  • b) the pole strength of the magnet
  • c)the horizontal component of magnetic field of earth
  • d)torsional rigidity of the suspension
Q.6
The relationship between µr and Χ ( chi) is
  • a) µr=1 + Χ
  • b) Χ=µr + 1
  • c)Χ=µrµo
  • d)Χ=µr/µo
Q.7
Metals getting magnetized by orientation of atomic moments in external magnetic field are called
  • a) diamagnetic's
  • b) paramagnetics
  • c) ferromagnetics
  • d) antimagnetic
Q.8
When a diamagnetic substance is brought near N or S pole of a bar magnet it is [ EAMCET 1995]
  • a)Attracted
  • b) Repelled
  • c)Attracted by N and repelled by S pole
  • d)Repelled by N pole and attracted by S pole
Q.9
Two short magnets are placed on a piece of cork which floats on water. The magnets are so placed that the axis of one produced bisects the axis of the other at right angle. then the cork
  • a) rotates only
  • b) moves bodily only
  • c)has neither transnational nor rotational motion
  • d)has transnational as well as rotational motion
Q.10
The magnetic field due to a magnetic dipole of magnetic moment M at a point at a distance d from its centre on a line inclined at an angle θ with the axis is given by
  • d)(M/d3) √( 1+3cos2θ)
  • a) M/d³
  • b) M/d²
  • c)2M/d³
Q.11
I is the total intensity of earth's magnetic field, H its horizontal component and V the vertical component, then these are related as
  • a) I=V2 + H2
  • b) I=V + H
  • c) I2=V + H
  • d) I2=V2 + H2
Q.12
A compass needle is placed at the magnetic pole. the compass needle [ CET 1994]
  • a)points south-east
  • b) points east-west
  • c)may stay in any direction
  • d)becomes vertical
Q.13
The magnetic susceptibility for diamagnetic material is [ AMU 1995]
  • a) small and negative
  • b) small and positive
  • c)large and positive
  • d)large and negative
Q.14
A steel wire of length l has a magentic moment M. It is bend into a semicircular arc. the new magnetic moment is .. [ BHU 1995]
  • a)M
  • b)2M/π
  • c)M/l
  • d)M × l
Q.15
The angle of dip is θ at a place where the horizontal and vertical components of earth's magnetic field are equal. the value of θ is [ SCRA 1994]
  • a) 0°
  • b) 30°
  • c) 45°
  • d) 60°
Q.16
A sample of cast Iron exhibits a magnetic field B=0.5 T, where the magnetic intensity H=10 A/m. At this value of M, the permeability of cast Iron will be
  • a) 0.5 T/mA
  • b) 5 TA/m
  • c)0.5T/mA
  • d)5TA/m
Q.17
The temperature at and above which a ferromagnetic material becomes paramagnetic is called [ SCRA 1994]
  • a) critical temperature
  • b) inversion temperature
  • c)Curie temperature
  • d)Debye temperature
Q.18
The hysteresis cycle for the material of transformer core is
  • a) short and wide
  • b) tall and narrow
  • c) tall and wide
  • d) short and narrow
Q.19
Magnetic field is caused by
  • a)stationary charge
  • b) a moving positive charge only
  • c)a moving negative charge only
  • d)moving positive and negative charges both
Q.20
Magnetic permeability is maximum for
  • a) diamagnetic
  • b) paramagnetic's
  • c)ferromagnetic
  • d)none of the above
Q.21
A magnet is placed horizontally on a paper. Then the neutral point obtained on the paper is
  • a) 1 only
  • b) 2
  • c)3
  • d)0
Q.22
Susceptibility is positive and large for [ BHU 1995]
  • a) paramagnetic substance
  • b) ferromagnetic substance
  • c) diamagnetic substance
  • d) non-magnetic substance
Q.23
The magnetic field due to a short magnet at a point in tanA position ( end position) is 200 gauss. Then the magnetic field at the same distance in tanB position ( broad side - on position) is
  • a)200 gauss
  • b) 400 gauss
  • c)50 gauss
  • d)100 gauss
Q.24
Magnetic field produced by electrons in atoms and molecules is due to their
  • a) spin motion only
  • b) orbital motion only
  • c)spin and orbital motion
  • d)neither spin nor orbital motion
Q.25
A bar magnet of magnetic moment M is placed in a uniform magnetic field of induction B such that it makes an angle θ with B. Then the position of stable equilibrium of magnet is given by θ equal to
  • a) zero
  • b) 45°
  • c)90°
  • d)180°
Q.26
The magnetic moment of atomic hydrogen is equal to
  • a) zero
  • b) ½ µB
  • c) µB
  • d) (3/2)µB
Q.27
A permanent magnet
  • a)attracts all substances
  • b) attracts only ferromagnetic substances
  • c)attracts ferromagnetic substances and repels all others
  • d)attracts some substances and repels other
Q.28
An isolated magnetic dipole is
  • a) a fictitious quantity
  • b) is made of soft iron only
  • c)is made of any ferromagnetic material
  • d)is made of any diamagnetic material
Q.29
The angle of dip is the angle
  • a) between the vertical component of earth's magnetic field and magnetic meridian
  • b) between vertical component of earth's magnetic field and geographic meridian
  • c)between earth's magnetic field direction and horizontal direction
  • d)between the magnetic meridian and geographic meridian
Q.30
The line joining the points of zero horizontal components of earth's field is called [ MNR 1987]
  • a) magnetic meridian
  • b) magnetic axis
  • c) magnetic line
  • d) magnetic equator
0 h : 0 m : 1 s