OK, minus nine equals zero, right.

好，减9等于0。好了。

To make time equal zero, you'd have to travel indefinitely fast.

为了使时间等于零，你必须非常快速地移动。

The two signals meet up in the corpus callosum and T equals zero.

这两个信号在胼胝体中汇合而T就等于零了。

But here, the integral will always equal zero for a closed surface.

但在这里，对于闭合曲面，积分始终为零。

So, the integral for side three equals zero.

因此，第三边的积分等于零。

That means the force on the left side minus  the force on the right side equals zero.

这意味着左侧的力减去右侧的力等于零。

And the force on the back side minus the  force on the front side also equals zero.

背面的力减去正面的力也等于零。

So, the integrals for sides two and four also equal zero.

因此，第二边和第四边的积分也等于零。

It’s Kirchhoff’s Loop Rule, and it says that the sum of all changes in potential around a loop equals zero.

这是基尔霍夫的循环规则， 它说循环周围所有电位变化的总和等于零。

It's Kirchhoff's Loop Rule, and it says that the sum of all changes in potential around a loop equals zero.

这是基尔霍夫循环规则，它表示 循环周围所有电位变化的总和为零。

And the net magnetic field outside an ideal solenoid equals zero because those magnetic fields are equal in magnitude and opposite in direction.

理想螺线管外部的净磁场为零，因为这些磁场大小相等且方向相反。

But, uh … Side 3 is completely outside the solenoid, and we now know that the magnetic field outside a solenoid equals zero.

但是， 呃… … 第 3 面完全位于螺线管外部，我们现在知道螺线管外部的磁场为零。

And ds is in the same direction as the magnetic field, so the angle theta equals zero degrees, and the cosine of zero degrees equals 1.

而ds与磁场方向相同，因此角度θ等于0度，0度的余弦等于1。

When the girl at rest, velocity equals zero miles per hour, begins accelerating to reach the speed within seconds, velocity increases rapidly to 25,000 miles per hour, her brain would crash into the side of her skull.

当这女孩处于静止状态时，时速为零。然后她突然在数秒内开始加速到两万五千里每小时，她的大脑会撞到头骨的一边。