In using tackle blocks it is important to select the ____ first.

• A. Blocks
• B. Ropes
• C. Sheaves
• D. Pulleys

Answer: (A)

Choosing the blocks first sets how the tackle will behave and how much load it can safely handle. The block arrangement—the number of sheaves and how they’re paired—determines the mechanical advantage, how many rope segments share the load, and how the rope will travel through the system. Once you know that, you can size the blocks to fit the load and space, and then pick rope that fits the groove sizes and provides the needed strength and length. If you start with rope or the pulleys separately, you may end up with a system that doesn’t fit together or meet the required performance. The blocks are the primary components that establish the system’s capability, so they’re selected first.