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我们知道,人站在雪地里,在雪地上就会留下深深的脚印,甚至会陷进雪地里,但如果人穿上滑雪板后再站在雪地里,就不会陷进雪里了(如图1).同样的压力对雪地的作用效果却不一样.另外.不同的人穿上相同的滑雪板后,在雪地表面留下的压痕也是不一样的.这是什么原因呢?因此,我们不难猜想,压力的作用效果可能和压力的大小及受力面积的大小有关.如何来验证这个关系呢?实验目的:探究压力的作用效果与什么因素有关.实验器材:海绵、小桌、砝码.实验步骤及方法:1.把小桌的桌腿朝下压在海绵上(如图2甲),小桌对海绵的压力就是小桌自身的重,即F=G_(桌).观察海绵的形变程度.2.不改变小桌的放置方式,在小桌上加放一个砝码(如图2乙).此时小桌对海绵的压力变成了小桌和砝码所受的重力之和,即F=G_(桌)+G_(砝码).小桌对海绵的压力增大后,观察到海绵的形变程度更大了.3.将小桌倒置,桌面与海绵接触,再在小桌上加放砝码(如图2丙).与图2乙比较起来,观察到海绵
We know that when people stand in the snow, they have deep footprints in the snow and can even get stuck in the snow, but if they sit in the snow after they wear the snowboard, they will not fall into the snow (Figure 1). The same pressure on the snow effect is not the same. In addition, different people wear the same snowboard, leaving indentation in the snow surface is not the same. The reason? Therefore, we can easily guess that the effect of the pressure may be related to the size of the pressure and the size of the affected area.How to verify this relationship? The purpose of the experiment: to explore the effect of stress and what factors.Experimental equipment: Sponge, small table, weight. Experimental steps and methods: 1. The small table legs down on the sponge (Figure 2 A), the pressure of the small table on the sponge is the weight of the table itself, that is, F = G_ (table) to observe the degree of deformation of the sponge .2 do not change the placement of small table, put a weight on the table (Figure 2 B). At this time the pressure of the table on the sponge into a small table And the weight of the weight received by the sum, that is, F = G_ (table) + G_ (weight) Table small sponge pressure increases, the sponge deformation is observed to a greater extent.3 Place the table upside down, the table top in contact with the sponge, and place the weight on the table (Figure 2c). As compared to Figure 2, a sponge