JEE Main 2023 — Solid State Question with Solution

A face-centered cubic (fcc) unit cell contains a component in the center of each face in addition to those at the corners of the cube. The atoms touch each other along the face diagonal.

For $\mathrm{FCC}: \mathrm{a}\sqrt{2}=4\mathrm{r}$

$\mathrm{a}=2\sqrt{2}\mathrm{r}$

A body-centered cubic (bcc) unit cell contains a component in the center of the cube in addition to those at the corners of the cube. The atoms touch each other along the body diagonal.

For $\mathrm{BCC} : \mathrm{a}\sqrt{3}=4\mathrm{r}$