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In physics, pressure depends on the amount of force acting on a surface and on the size of the surface.
物理學(xué)上，壓力大小取決于作用在表面力的大小和表面積大小。
The smaller the surface, the greater the pressure.
表面積越小，承受的力越大。
Let's say that a woman steps on your toe; she weighs 120 pounds.
假設(shè)一個(gè)重120磅的女人踩到你腳趾了。
If she's wearing flat shoes, you would feel the force of 120 pounds spread out over the whole heel of the shoe, maybe around 4 square inches.
如果她穿的是平底鞋，你會(huì)感到120磅的壓力分散到鞋子的整個(gè)根部，大概4平方英寸。
So the pressure would be 120 divided by 4, or 30 pounds per square inch.
所以120磅的壓力平均分為4份，或者每平方英寸30磅的力。
But when she steps on you with a high heel, the whole 120 pounds of force is concentrated on a heel that is maybe one eighth of one square inch in area.
但如果她穿的是高跟鞋，整個(gè)120磅的力集中在或許只有八分之一英寸大小的鞋跟上。
Now the pressure of her step is eight times as much, or 240 pounds per square inch instead of 30 pounds per square inch.
她踩下去的壓力也是8倍之多，或者說240磅每平方英寸而不是30磅每平方英寸。
Of course, it hurts more.
當(dāng)然，這更痛。
It works the other way, too.
同理，
Spiked heels are painful to wear because your weight is all on the spike and the ball of the foot;
穿細(xì)高跟鞋是痛苦的，因?yàn)槟愕闹亓咳珘涸谠诩?xì)跟和腳趾球上。
therefore, the pressure is much greater on these points than in running shoes, where your weight is spread out over the whole bottom of the foot.
因此，壓力在這些點(diǎn)上要比重量被分散在整個(gè)腳底的跑鞋大很多。
