问题:均匀磁场对载流导体的作用力的通用表达式为F=BILsinQ...
Thursday, September 15, 2022
Monday, September 12, 2022
问题:试验证明温度在()℃范围内金属导体的电阻随温度成正比变化。A、20~80B、25~75C、0~85D、0~100...
Wednesday, March 20, 2024
问题:井下防爆型的通信、信号和控制等装置,应优先采用()型。A、隔爆B、本质安全C、防爆特殊...
Tuesday, March 28, 2023
Thursday, September 15, 2022
Monday, September 12, 2022
Sunday, September 11, 2022
Monday, September 12, 2022
问题:摩擦轮传动,主要适用于高速,小功率的传动场合。()...
Friday, September 16, 2022
Thursday, September 15, 2022
问题:矿井提升防坠器每()进行一次脱钩试验。A、三个月B、半年C、一年D、一年半...
Friday, November 10, 2023
Monday, September 12, 2022
Monday, September 12, 2022
问题:井下摇测接地电阻必须使用ZC—8型接地电阻测试仪。...
Friday, September 16, 2022
问题:()由地面中性点直接接地的变压器或发电机直接向井下供电。Q...
Monday, September 12, 2022
问题:故障诊断技术是一门综合性科学,涉及多方面的知识和技术。...
Thursday, September 15, 2022
Thursday, September 15, 2022
问题:把交流电一次周期性变化所需时间叫做交流电的()。...
Thursday, September 15, 2022
问题:设某一电容器任一极板上的电量为4e,两极间的电压为2V,则其电容...
Thursday, September 15, 2022
Thursday, September 15, 2022