A cable has to be held up by something suitable, and kept away from anything that can damage it.
Unsupported cable takes its weight on its own terminations. Unprotected cable meets whatever the building does to it later -- a screw, a sharp edge, a foot.
Two separate problems with two separate answers. Support is about weight and strain: the cable hangs from its supports rather than from the connections at each end. Protection is about what else is in the building: a sharp metal edge, a place things get stored against, a spot somebody will drive a fastener into later.
Check yourself: A cable passes over a sharp metal edge but is not touching it hard. Is that acceptable?
Answer: No. A sharp metal edge calls for an approved protection method.
The edge does not have to be cutting the cable today. Movement, vibration and time bring it into contact, and the protection is what stops that being a problem later.
No card. No account needed to start. Score by topic against the 70% mark.
Written from the owner's poster for this lesson. Nothing added beyond what the poster states.
Written for Texas apprentices as free study material. The Texas apprentice licence is an application, not an exam (Occupations Code 1305.161), and nothing here counts as apprenticeship hours or continuing-education credit. VoltMark is not affiliated with, endorsed by, or sponsored by NFPA, PSI, TDLR, or any state or local licensing authority. Always follow your employer's safety programme and your supervising electrician.
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