23528.A particle of charge –16 × 10–18 coulomb moving with velocity 10 ms–1 along the x–axis enters a region where a magnetic field of induction B is along the y–axis, and an electric field of magnitude 104 V/ m is along the negative z–axis. If the charged particle continues moving along the x–axis, the magnitude of B is
10–3 Wb/m2
103 Wb/m2
105 Wb/m2
1016 Wb/m2
23529.A magnetic needle is kept in a non–uniform magnetic field. It experiences
a torque but not a force
neither a force nor a torque
a force and a torque
a force but not a torque
23530.At certain place, the horizontal component of earth’s magnetic field is 3.0 G and the angle dip at the place is 30°. The magnetic field of earth at that location
4.5 G
5.1 G
3.5 G
6.0 G
23531.Curie temperature is the temperature above which
a ferromagnetic material becomes paramagnetic.
a paramagnetic material becomes diamagnetic.
a ferromagnetic material becomes diamagnetic.
a paramagnetic material becomes ferromagnetic.
23532.Electromagnets are made of soft iron because soft iron has
high susceptibility and low retentivity
low susceptibility and high retentivity
low susceptibility and low retentivity
high susceptibility and high retentivity
23533.If an electron and a proton having same momenta enter perpendicularly to a magnetic field, then
curved path of electron and proton will be same (ignoring the sense of revolution)
they will move undeflected
curved path of electron is more curved than that of the proton
path of proton is more curved
23534.Core of electromagnets are made of ferromagnetic material which has
low permeability and high retentivity
high permeability and low retentivity
low permeability and low retentivity
high permeability and high retentivity
23535.For diamagnetic materials, magnetic susceptibility is
small and negative
small and positive
large and negative
large and positive
23536.At a specific instant, emission of radioactive compound is deflected in a magnetic field. The compound can emit
(i) electrons
(ii) protons
(iii) He2+
(iv) neutrons
The emission at instant can be
(i) electrons
(ii) protons
(iii) He2+
(iv) neutrons
The emission at instant can be
i, ii, iii
i, ii, iii, iv
iv
ii, iii
23537.The magnetic susceptibility of a paramagnetic material at –73°C is 0.0075 and its value at –173°C will be
0.015
0.0045
0.0075
0.0030