What is the purpose of the limit switch on gravity davits?（）
尿比重（urinaryspecific gravity，SG）
A virtual rise in the center of gravity may be caused by（）.
使用粒子工具Particle Tool在网格平面上创建一个网格状分布的栅格粒子particle1，然后通过执行Ctrl+D复制一个粒子particle2，选择两个粒子，添加重力场Gravity，结果particle1下落，而particle2没有下落，原因是（）。
A crankshaft whose center of gravity coincides with its center line is said to be （）.
The distance traveled by the center of gravity perpendicular to the original course is（）.
Stability is determined principally by the location of the center of gravity and the（）.
A virtual rise in the center of gravity of a ship may be caused by（）.
A vertical shife of weight to a position above the vessel''s center of gravity will（）.
The maximum speed of lowering for a lifeboat on gravity davits is controlled by the（）.
For a purifier changing to a gravity disc with smaller hole diameter will move the interface towards the（）.
The specific gravity of fuel oil is a （）.
重力坝（gravity dam）
Which sequence is correct when launching a lifeboat stowed in gravity davits?（）
Stability is determined by the relationship of the center of gravity and the（）.
1963年（）制作了第一部计算机动画片"Two gyro gravity gradient attitude control system"。
Limit switches on gravity davits should be tested by（）.
High-speed rotating in a centrifugal purifier can produce a force （） larger than the force of gravity.
In the absence of external forces，the center of gravity of a floating vessel is located directly above the（）.
High-speed rotation in a centrifugal purifier can produce a force （） the force of gravity.
15、在常见的三种力中，第一种是万有引力，万有引力与重力的关系是___ Of the three common forces, the first is Universal Gravitation, and the relationship between Universal Gravitation and Gravity is___
The moon’s surface gravity is only about____as strong as the earth’s surface gravity.
Once out of the earth’s gravity, the astronaut is ________ by the problem of weightlessness.
Gravitys Rainbow is written by
