Question

In simple cubic unit cell distance between first and fourth layer :-(1) 4 r(2) 2 r(3) 6 r(4) None of these

Answer 1

The explanation for the correct option:

Option(3) 6r

• ​A simple cubic unit cell has 8 atoms in each corner of the cube, and that atom is shared with 8 neighboring cells.
• Since all the sides of the cube are equal, with a length say 'a'.
• Hence the distance between each layer of the cubic unit cell is a.
• where it is given that $a=2r$
• So the distance between the first layer and the fourth layer is $3a=3\times 2r=6r$

Hence, Option(3) 6r is the distance between the first and fourth layers in a simple cubic unit cell.