爆炸點解會做成傷害？

最簡單既爆炸, 就係點火柴.

係原始點, 利用動能 / 電能 / 位能等能量既引發, 會將物體既結構破壞, 從而放出能量, 如果能量係放出熱能就會覺得熱, 而相反係轉變為另一狀態中就會吸收熱 (即係冷)

而如果爆炸點的物體會破裂而彈出, 咁更加有動能上附加於物體上既傷害 (比如破碎片飛出)

First, read the following to understand explosion:

https://zh.wikipedia.org/zh-hk/%E7%88%86%E7%82%B8

In answering your questions:

1-2. Due to the explosion, material nearby will be transformed to kinetic energy. The more powerful the explosion, the larger the kinetic energy. This energy is what causes the damages.

For example, excluding the debris, the explosion will transform the nearby air into kinetic energy. This is why most windows nearby an explosion scene are usually broken.

3. It varies.

爆炸是空氣高速膨漲，令爆炸附近異物分離，爆石就是好例子，爆石要先在石上鑽一洞，放入炸藥，燃點炸藥產生高熱令空氣高速膨漲，將石頭爆開。