Question 392 Deck General

The correct answer is C) The stress on the head block is greater at 60°. As the boom angle increases from 20° to 60° relative to the horizontal, the vertical component of the weight being lifted increases, resulting in greater stress on the head block. At 60°, the vertical force component is greater than at 20°, leading to higher stresses on the head block. The other answer choices are incorrect because: A) The thrust on the boom is actually greater at 60° due to the increased vertical force component. B) The stress on the heel block would be lower at 60° as the horizontal force component decreases. D) The angle of elevation does change the stresses in the masthead fairlead for the topping lift, as the vertical force component increases with a higher boom angle.