A system of two blocks of masses $m=2 \mathrm{kg}$ and $M=8 \mathrm{kg}$ is placed on a smooth table as shown in figure. The coefficient of static friction between two blocks is $0.5$. The maximum horizontal force $F$ that can be applied to the block of mass $M$ so that the blocks move together will be $\left(g=9.8 \mathrm{m} {\mathrm{s}}^{-2}\right)$