With a given load on the cargo hook, tension...

🔍 Key Concepts

• Boom geometry – how the angle of the boom to the horizontal changes the direction of forces • Vector components of force – how the cargo weight is shared between the topping lift and the boom as the angle changes • Tension vs. angle – how vertical and horizontal components of the topping lift tension vary as the boom raises or lowers

💭 Think About

• Imagine the boom nearly horizontal: how much of the cargo weight must be supported by the topping lift versus the boom itself? • Now imagine the boom nearly vertical: how does the direction of the topping lift compare to the direction of the cargo weight? • As the boom moves from horizontal toward vertical, does the topping lift have to "pull" more directly against the weight, or less?

✅ Before You Answer

• Keep the load on the cargo hook constant in all comparisons • Focus on the vertical component of the topping lift tension needed to balance the cargo weight • Be clear on which way the phrase "angle to the horizontal" is measured and how that changes from small (near horizontal) to large (near vertical) angles

With a given load on the cargo hook, tension in a single span topping lift __________.

increases as the boom's angle to the horizontal decreases

increases as the boom's angle to the horizontal increases

is at a maximum when the boom is at a 45° angle to the horizontal

decreases as the boom's angle to the horizontal decreases

🔍 Key Concepts

💭 Think About

✅ Before You Answer