Surface Tension and Viscosity: Practice Problem & Solution

Solution Explained:

To solve this problem, we apply the core principles of Surface Tension and Viscosity. Understanding the underlying formula is key to arriving at the correct answer below:

Rate of heat production $P = F_v v_t$. We know $F_v = 6\pi\eta r v_t$ and $v_t \propto r^2$. Thus, $$P = (6\pi\eta r v_t) v_t \propto r (r^2)^2 \propto r^5$$.