$($b$)$ Maize grain is ground from a size of which it is acceptable that $80\%$ pass a $10$ mm sieve

down to a size in which it is acceptable that $80\%$ passes a $0\mathrm{.}5$ mm sieve, and a $5-$horsepower

motor is found just sufficient for the required throughput. If the requirements are changed

such that the grinding is only down to $80\%$ through a $2$ mm sieve but the throughput is to be

increased by $50\%$ would the existing motor have sufficient power to operate the grindner?

Assume Bond's equation.

$E=2K[\frac{1}{(x_2{)}^{\frac{1}{2}}}-\frac{1}{(x_1{)}^{\frac{1}{2}}}]$

Where:

$x_1$ and $x_2$ are measured in micrometjers. $E$ is in kWh short $to{n}^{-1}(907\mathrm{.}16kg).K=5E_i.E_i=$

Bond Work Index $-$ the energy required to reduce unit mass of material from an infinite

particle size to a size such as that $80\%$ passes a $100m$ sieve. $E_i$ is obtained from laboratory

crushing tests on the feed material.

$[12$ marks$]$In