单项选择题

For any given pedestal crane，when the boom is lengthened，the lifting capacity is（）.

A.unchanged
B.increased
C.eliminated
D.decreased

点击查看答案&解析

上一题目录下一题

相关考题

单项选择题

For a given weight of cargo，the stress on the heel block of a cargo boom（）.

A.increases as the cargo closes the head while hoisting
B.increases if the cargo runner is doubled up
C.decreases as the boom is topped to a greater angle
D.is determined by the thrust stresses on the boom

单项选择题

Bonding cables are used during cargo transfer to（）.

A.provide safe electrical power connection to barge equipment
B.keep the vessel from surging excessively
C.prevent an accidental discharge of static electricity
D.secure the cargo hose to a hatch when loading overall

单项选择题

Backstays are（）.

A.running rigging leading aft from the masts
B.running rigging leading forward from the masts
C.standing rigging leading aft from the masts
D.standing rigging from the cross trees to the mast head