Figure 1 shows the cross-section of a hybrid biomedical micro-electrode cable used for localized high-frequency thermal ablation.
The cable consists of a central titanium core that provides structural rigidity, surrounded by eight thin copper conductor strands that deliver the electrical power. Both the titanium core and the individual copper strands run parallel to each other along the entire length of the cable and are connected to the same voltage source at each end.
A 15 cm length of the central titanium core has a much higher electrical resistance than a 15 cm length of a single copper strand.
Explain why the current flowing through the titanium core is significantly smaller than the current flowing through any single copper strand.