Answer
4.1 mV
Work Step by Step
First, find the resistance between the bird’s feet.
$$R=\frac{2.5\times10^{-5}\Omega}{m}(4.0\times10^{-2}m)=1.0\times10^{-6}\Omega$$
Next, use equation 18–2, which defines the resistance, to find the potential difference.
$$V=IR=(4100A)( 1.0\times10^{-6}\Omega)= 4.1\times10^{-3}V$$
