Which force is the pulling or stretching force that creates outward movement away from the center?

• A. Tension
• B. Gravity
• C. Load
• D. Compression

Answer: (A)

Tension is the pulling or stretching force that tends to elongate a member by pulling its ends away from the center. This is why it causes outward movement along the length—the material is stretched as opposite ends pull outward.

Gravity, by contrast, pulls toward the center of the Earth, not along the member to cause it to lengthen. A load is a general term for forces acting on a member and can be in tension, compression, or shear depending on the situation, so it’s not specific to outward pulling. Compression does the opposite of tension, pushing toward the center and shortening the member.

An everyday example is a suspension bridge cable under tension, where the cable pulls at its ends away from the center, keeping the bridge deck supported.