12. The coordinates of a lattice site nearest to the origin is given by x = −2a,
y = 1b and z ¼
3c
2 : the Miller indices of its direction are:
(a) 4 23
½
Š
(b) 423
½
Š
(c) 213
½
Š
(d) 1 23
½
Š
13. The direction that connects the origin and the point
1
3
1
3
2
3
 Ã
Â
Ã
is:
(a) [211]
(b) [121]
(c) [112]
(d) [123]
14. [211] is the direction that connects the origin and the point:
(a) [112]
(b) [121]
(c) 11
1
2
Â
Ã
(d) 1
1
2
1
2
Â
Ã
15. The number of crystallogaphically equivalent directions in the <100> family of
a cubic crystal system is:
(a) 4
(b) 6
(c) 8
(d) 12
16. The number of crystallogaphically equivalent directions in the <110> family of
a cubic crystal system is:
(a) 4
(b) 6
(c) 8
(d) 12
17. The number of crystallogaphically equivalent directions in the <111> family of
a cubic crystal system is:
(a) 4
(b) 6
(c) 8
(d) 12
4.5 Zone and Zone Axis
171