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+### Statement
+
+$8.2.17.$ [Insert the problem statement]
+
+### Solution
+
+### Statement
+
+$8.2.17.$ A metal ball of radius $r$ is located in a medium with a small conductivity $\lambda$. Determine the current flowing from the ball if its potential is $V$. If such a ball is connected by an insulated wire to a lightning rod, what will be the grounding resistance?
+
+### Solution
+
+Current will flow from the metal ball due to charge leakage into the conducting medium. The current density on the surface of the ball is:
+
+$$j = \lambda E$$
+
+where $E$ is the electric field strength on the surface of the ball.
+
+The potential of the ball is related to the electric field strength on its surface:
+
+$$E = \frac{V}{r}$$
+
+Then:
+
+$$j = \lambda \frac{V}{r}$$
+
+The current flowing from the surface of the ball is:
+
+$$I = j \cdot S = \lambda \frac{V}{r} \cdot 4\pi r^2 = 4\pi\lambda rV$$
+
+If the ball is connected by an insulated wire to a lightning rod (which has the potential of the Earth), then the grounding resistance is:
+
+$$R = \frac{V}{I} = \frac{V}{4\pi\lambda rV} = \frac{1}{4\pi\lambda r}$$
+
+#### Answer
+
+$$I = 4\pi r\lambda V$$
+
+$$R = \frac{1}{4\pi r\lambda}$$
+
+#### Answer
+
+[Insert a concise answer or boxed result]