A uniform chain of length $2.0\ \text{m}$ and mass $4.0\ \text{kg}$ lies partly on a rough horizontal table, and the rest hangs over a smooth, rounded edge, as shown in the figure. The coefficient of sliding friction between the chain and the table is $0.2$. The chain is sliding off the table. At the instant when $0.8\ \text{m}$ of it hangs, what is the tension in the chain at the edge of the table? Take $g = 10\ \text{m/s}^2$.

Fig. 1: A uniform chain lies straight along a table, 1.2 m of it on the table top, where the friction coefficient is 0.2. The remaining 0.8 m hangs straight down over the smooth rounded right edge of the table.