无码高清视频|成人自拍视频|欧美成人午夜无码A片秀色直播|草美女视频网站|美女被操网站在线观看

<ruby id="bm1j8"><small id="bm1j8"></small></ruby>

單項(xiàng)選擇題

If a DC motor runs hot, the cause may be （）

A.high mica condition
B.low ambient temperature
C.clogged ventilation ducts
D.an open in the shunt field

你可能感興趣的試題

單項(xiàng)選擇題

The unit of electrical resistance is the （）

A.ampere
B.volt
C.watt
D.ohm

單項(xiàng)選擇題

Some large A-Cmotors are equipped with heatersThese could be （）
(1)resistance heaters bolted directly to the frame
(2)low voltage windings embedded in the motor windings

A.(1) only
B.(2) only
C.either (1) or (2)
D.neither (1) or (2)

<ruby id="35msn"><output id="35msn"></output></ruby>

<ins id="35msn"></ins>

<blockquote id="35msn"></blockquote>