题干

某居民早起忘记关闭电褥子的电源就去上班,下班后发现卧室门缝冒出黑烟,他立即打开门窗,结果原本只冒黑烟的电褥子瞬间燃起火焰.

(1)分析产生上述现象的原因.

(2)电褥子着火,应采用什么方法灭火?

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答案(点此获取答案解析)

(1)长时间充电会导致电褥子过热,温度达到可燃物的着火点引发燃烧,但是卧室内氧气不充足,所以冒黑烟,当打开门窗时,空气流通,空气中氧气含量增加,所以迅速燃烧;

(2)为了防止触电,在灭火前应先切断电源,然后再用水浇灭.

同类题3

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