## Physics: Principles with Applications (7th Edition)

$2.4 \times 10^{-2}N/m$
As explained in the text, in figure 10–34 there is both a top and a bottom surface. $$\gamma = \frac{F}{2 \mathcal{l}}$$ $$\gamma=\frac{3.4 \times 10^{-3}N}{2(0.070m)}=2.4 \times 10^{-2}N/m$$