为什么没有开封的网球可以保持良好的硬度和弹跳,而开罐后的网球就会随着时间的推移越来越软,弹跳也越来越低?因为这类罐装网球采用的是加压制造和包装技术,球体和球罐里的气压比大气气压高一些。当开罐之后,球体的内外气压趋于平衡,因此慢慢就软了下来。这类网球称之为有压网球,通常职业比赛都采用这类网球。在比赛前七局 Why is there no opening of the tennis ball can maintain a good hardness and bounce, and the canned tennis will be more and more soft over time, bouncing is getting lower and lower? Because this type of canned tennis is used to create pressure And packaging technology, the ball and the tank pressure is higher than the atmospheric pressure. When the can is opened, the pressure inside and outside the sphere tends to be balanced and therefore slowly softens. This type of tennis is called tennis, often used in professional games such tennis. In the first seven games