【名词&注释】
过电压、单相接地(single phase grounding)、变压器(transformer)、电磁冲击力(electromagnetic force)、额定功率(rated power)
[单选题]异步电动机额定转矩TN与额定功率(rated power)PN和额定转速nN的关系为()kg.m。
A. TN=975PNnN B. TN=PN/nN C. TN=975PN2/nN D. TN=975PN/nN