According to Bond crushing law, the work required to form particle of size $\text{'}$D$\text{'}$ from very large feed is $($where $($S$/$V$)$p and $($S$/$V$)$f are surface to volume ratio of the product and feed respectively$).$

$($S$/$V$)$p

$($S$/$V$)$p

$($S$/$V$)2$ p

$($S$/$V$)$f