The answer is in the center of mass.

答案就是质心。

Human being center of mass rest between their legs, your hips.

人的重心在两腿之间，臀部之间。

In reality, both circle around their mutual center of mass, located between the two.

事实上，两者都围绕着位于两者之间的相互质心旋转。

These are sets of two stars that orbit around a common center of mass.

即由两颗恒星组成的组合，它们围绕一个共同的质心运行。

The planets and Sun are orbiting, what we call their common center of mass.

行星和太阳都在绕轨道运行，我们称之为它们的共同质量中心。

To make your opponent unstable, you have to move his or her center of mass.

要使你的对手不稳定，你必须移动他或她的重心。

Three times heavier and the center of mass will be three times closer. And so on.

重三倍，质心的位置就进三倍，以此类推。

Within a given supercluster, all galaxy motions will be directed inward, toward the center of mass.

而在超星系团内部，所有星系都是向内部质心运动。

There's a simple way to figure out where the center of mass is.

有一个简单的方法找出质心。

The future device would quickly rearrange or even eject internal components to change its center of mass.

这款未来电子设备将能够在最短时间内进行重新排列或弹出内部组件以改变重心。

With a low center of mass, the wheel just swings back and forth like a pendulum, then stops.

当质心较低时，车轮就像钟摆一样来回摆动，然后停止。

And yet, collected together, they have a single total amount that they spin about their center of mass.

但聚集在一起时，它们有一个单一的总的不变量，他们总是围绕着它们的质心旋转。

If you can getthe center of mass to be over the pivot point, the seesaw will be balanced.

如果找到了是新的支点，跷跷板就平衡了。

And the thing about pommel horse is like you're feeling how your center of mass sort of swivels around.

而且你能感觉到自己的重心在旋转。

By standing in the stirrups for the entire ride, a jockey's center of mass follows an almost flat line.

骑手全程都踩着马镫站立，其重心几乎可以保持一条水平线。

The stars all orbit the cluster's center of mass, even though there may not be anything at the very center.

所有的恒星都围绕着星团的质心旋转，即使在最中心可能没有任何东西。

The moving parts that make one side of the wheel heavier also shift its center of mass downward below the axle.

使车轮一侧更重的运动部件也将其质心向下移至车轴下方。

An important thing to note is that we measure gravity from the center of mass of an object, not its surface.

需要注意的一件重要的事情是，我们测量引力是从一个物体质量的中心点开始的，而不是从它的表面开始。

The center of mass is a pointsomewhere along the plank that holds the two kids where their average weight falls.

质心是跷跷板上支撑两个孩子平均重量的一个点。

To make the seesaw work, theheavy kid must push that center of mass forward until it just touches the pivot.

要想让跷跷板摇动，重的孩子就得往中间挪直到质心移到中心。