What is the primary reason for using shielding in cables?

Using shielding in cables primarily serves to protect against electromagnetic interference (EMI). Cables are often exposed to various electromagnetic fields generated by nearby electronic devices, power lines, and radio signals. If a cable is not shielded, these external electromagnetic signals can couple into the conductive pathways within the cable, causing disruption, noise, and interference in the transmitted signals.

By incorporating shielding—such as a metallic foil or braided wire layer around the cable—these unwanted signals can be blocked or significantly attenuated. This is particularly crucial in applications where signal integrity is vital, such as in telecommunications, audio/video transmission, and data communication, as it ensures that the transmitted signals remain clear and uncorrupted.

The other options touch on aspects that may influence cable design, such as aesthetics, flexibility, and weight, but they are not primary functions of shielding. Aesthetic appearance does not contribute to the performance of a cable, while flexibility and lightweight design are often achieved through different engineering approaches rather than shielding.