What protection method shields against electromagnetic or radio frequency interference?

What protection method shields against electromagnetic or radio frequency interference?

• A. Grounding
• B. Insulation
• C. Shielding
• D. Filtering

Answer: (C)

Shielding blocks electromagnetic and RF interference by surrounding the equipment or cables with a conductive or magnetic enclosure. This enclosure acts like a shield, reflecting and absorbing external RF energy so it cannot reach the sensitive circuitry inside, and it can also keep the device’s own emissions from leaking out. Grounding the shield helps drain any induced currents, boosting the protection. This approach is different from grounding alone (which provides a earth reference and fault path but doesn’t enclose and block fields), insulation (which prevents direct contact or breakdown but doesn’t reduce surrounding RF energy), or filtering (which targets noise on specific signal lines rather than shielding the whole enclosure). A practical example is a metal enclosure or shielded cable with a proper ground connection, forming a Faraday cage that attenuates external interference.

Shielding blocks electromagnetic and RF interference by surrounding the equipment or cables with a conductive or magnetic enclosure. This enclosure acts like a shield, reflecting and absorbing external RF energy so it cannot reach the sensitive circuitry inside, and it can also keep the device’s own emissions from leaking out. Grounding the shield helps drain any induced currents, boosting the protection. This approach is different from grounding alone (which provides a earth reference and fault path but doesn’t enclose and block fields), insulation (which prevents direct contact or breakdown but doesn’t reduce surrounding RF energy), or filtering (which targets noise on specific signal lines rather than shielding the whole enclosure). A practical example is a metal enclosure or shielded cable with a proper ground connection, forming a Faraday cage that attenuates external interference.