Lightning is a ________ of electrical current from a cloud to the ground or from one cloud to another.

A．) rush   B) rainbow       C) rack             D) ribbon

 

[试题]Lightningisa________ofelectricalcurrentfromacloudtothegroundorfromonecloudtoanother.A．)rushB)rainbowC．)rackD)ribbon

[主观题]Youseethelightning_________ithappens,butyouhearthethunderlater.A．)theinstantB)foraninstantC．)ontheinstantD)inaninstant

[单选题]英语ELECTRICAL指（）A .电动的B .气动的C .电磁阀D .转换器

[单选题]The unit of electrical power is the _____.A．ampereB．kilovoltC．wattD．farad

[单选题]The unit of electrical resistance is theA．ampereB．voltC．wattD．ohm

[单选题]A．n electrical device which prevents an action from occurring until all other required conditions are met is called a/an _____.A．limitB．monitorC．modulatorD．interlock

[名词解释] 电气装置（electrical installation）

[名词解释] 电气分隔（electrical separation）

[单选题]In Trial 9, the electrical force exerted by Sphere Y on Sphere X and the electrical force exerted by Sphere X on Sphere Y were exerted in which direction(s)?A．east； eastB．east； westC．west； westD．west； east

[名词解释] 电气设备（electrical equipment）