单项选择题
A.diode
B.transformer
C.transistor
D.rheostat
单项选择题 Which of the listed devices is used to measure pressure and convert it to an electrical signal?()
单项选择题 A direct current passing through a wire coiled around a soft iron core is the description of a simple().
单项选择题 Which of the following electric motors would be the safest and most reliable to use on the main deck of a vessel in foul weather conditions?()