Question

The correct relationships between unit cell edge length ‘a’ and radius of sphere ‘r’ for face-centred and body-centred cubic structures respectively are:

• A. $2\sqrt 2r = a$ and $4r = \sqrt 3 a$
• B. $r = 2\sqrt 2a$ and $\sqrt 3 r = 4a$
• C. $r = 2\sqrt 2a$ and $4r = \sqrt 3a$
• D. $r = 2\sqrt 2a$ and $\sqrt 3r =4a$

Answer 1

Answer: (A)

$2\sqrt 2r = a$ and $4r = \sqrt 3 a$

Answer 2

The correct option is (A): $2\sqrt 2r = a$ and $4r = \sqrt 3 a$