A ferromagnetic substance becomes a permanent magnet when it is placed in a magnetic field because:

1.	All the domains get oriented in the direction of the magnetic field.
2.	All the domains get oriented in the direction opposite to the direction of the magnetic field.
3.	Domains get oriented randomly.
4.	Domains are not affected by the magnetic field.

The correct order of the packing efficiency in different types of unit cells is-

1.  Fcc < Bcc < Simple cubic

2.  Fcc > Bcc > Simple cubic

3.  Fcc < Bcc > Simple cubic

4.  Bcc < Fcc > Simple cubic

Dislocation defect is also known as-

1. Frenkel defect.

2. Schottky defect.

3. Non-stoichiometric defect.

4. Simple interstitial defect.

In the cubic close packing, the unit cell has ......... .

The edge lengths of the unit cells in terms of the radius of spheres constituting fcc, bcc, and simple cubic unit cells are respectively -

1. $2\sqrt{2\mathrm{r}}, \frac{4\mathrm{r}}{\sqrt{3}}, 2\mathrm{r}$

2. $\frac{4\mathrm{r}}{\sqrt{3}}, 2\sqrt{2\mathrm{r}}, 2\mathrm{r}$

3. $2\mathrm{r}, 2\sqrt{2\mathrm{r}}, \frac{4\mathrm{r}}{\sqrt{3}}$

4. $2\mathrm{r}, \frac{4\mathrm{r}}{\sqrt{3}}, 2\sqrt{2\mathrm{r}}$

Correct statement among the following regarding conductivity in solids is -

1.   ${\mathrm{\kappa }}_{\mathrm{metals}} \gg {\mathrm{\kappa }}_{\mathrm{insulators}} < {\mathrm{\kappa }}_{\mathrm{semiconductors}}$

2.   ${\mathrm{\kappa }}_{\mathrm{metals}} \ll {\mathrm{\kappa }}_{\mathrm{insulators}} < {\mathrm{\kappa }}_{\mathrm{semiconductors}}$

3.   ${\mathrm{\kappa }}_{\mathrm{metals}} , {\mathrm{\kappa }}_{\mathrm{semiconductors}} > {\mathrm{\kappa }}_{\mathrm{insulators}} = \mathrm{zero}$

4.  ${\mathrm{\kappa }}_{\mathrm{metals}} < {\mathrm{\kappa }}_{\mathrm{semiconductors}} > {\mathrm{\kappa }}_{\mathrm{insulators}} \ne \mathrm{zero}$

Which of the following is not true about the voids formed in a 3-dimensional hexagonal close-packed structure?

The correct choice among the given is - 

1. (I, II)

2. (II, III)

3. (III, IV)

4. (I, III)

The value of the magnetic moment is zero in the case of antiferromagnetic substances because the domains -

The correct choice among the given is -

1. (I, II)

2. (II, III)

3. (III, IV)

4. (I, IV)

Incorrect(s) statement among the following:

1. (I, II)

2. (II, III)

3, (III, IV)

4. (I, IV)

The correct statements among the following about metals are-

1. (I, II, III)

2. (II, III, IV)

3. (I, III, IV)

4. (I, II, IV)