Whenever there's a Nick or hairlinecrack in an insulation sheath, the electrical field in the underlying copper subtly shifts.
在绝缘套上只要出现缺口或者毛细裂缝，线缆里的铜周围的电场就会轻微改变。
2
He seemed to be catching on nothing: propping his boot on a pimple, gripping a "smear" or a hairlinecrack, freeing both arms from the rock to make a lunge.
The moment that sensors detect a hairlinecrack anywhere in the aircraft, microscopic nano-capsules containing a high-tech adhesive would be released to seal the fissure.