来自《耶鲁大学开放课程：基础物理第4集第4集》

So the force of friction seems to depend on

所以摩擦力看起来取决于
how heavy the object is that's sitting on the table.

桌子上的物体有多重
But what does it not depend on that it could depend on?

但什么是它可能取决于但是并未取决于的因素呢
Can you think of something else it could depend on but doesn't?

你们能不能想出这样的因素呢
Yes?

说吧
It doesn't depend on the area of contact.

它并不取决于接触的面积
In other words,

换句话说
if this was a rectangular block,

如果这是一个矩形块的话
it doesn't seem to matter whether it's doing that

它这样放置还是这样放置
or whether it's doing that.

并没有区别
You might think,

你也许会想
"Hey, there's going to be more friction

"啊这个摩擦力会更大