春节时,小虎和爸爸妈妈一起回老家和爷爷奶奶过年。除夕夜,吃完团圆饭在院子里放焰火时,小虎突然看到邻居叔叔家的配电箱进户线处在不断地冒火花,还听到“嗤嗤嗤”的声音(如图所示)。邻居叔叔也不知道是怎么回事,爸爸说,那是因为进户线接触不良,当有风吹时电线产生抖动,使得接触情况变得更差,所以就会局部发热,并且冒出火花。爸爸边说着,边用一根干燥的木棒在进户线的接线柱 Spring Festival, the tiger and mom and dad together to go home and grandparents New Year. New Year's Eve, eating reunion dinner in the yard to put fireworks, the tiger suddenly saw the neighbor's uncle's power distribution box into the line at the constant sparks, but also heard “Chi Chi Chi” sound (Figure Shown). Neighbors uncle also do not know what's going on, my father said, it is because of poor access to line, when there is a wind blowing jitter, making the contact worse, it will heat locally, and sparks. Dad said while talking, with a dry stick at the entrance of the terminal