举一反三
- The instrument for measuring real power is the:
- _____is an instrument for measuring the vital capacity of the lungs .
- The effective value of ac voltage or current is（ ） A: The average value of a voltage or current B: DC equal to the AC thermal effect is defined as the effective value of AC C: voltage or current are 0.707 of their amplitudes D: closely related to the frequency of alternating current
- A major application of the diode is in the production of a dc voltage from an ac supply, ______ as rectification.
- 在NSTL(国家科技图书文献中心)检索题为“Temperature coefficient measuring methods of output voltage and output current for multi-junction solar cells and modules”的标准,标准号为:
内容
- 0
A laser can be best described by______. A: a device for stimulating atoms and molecules to emit light B: an atom in a high energy state C: a technique for destroying atom or molecules D: an instrument for measuring light waves
- 1
Which of the following statements best describes a laser A: A device for stimulating atoms and molecules to emit light. B: An atom in a high-energy state. C: A technique for destroying atoms or molecules. D: An instrument for measuring light waves.
- 2
For a neutral-unearthing system, during a bolted single line-to-ground fault, the non-fault phase voltage and the fault phase voltage are ()respectively. A: phase voltage and zero B: phase voltage and line-to-line voltage C: line-to-line voltage and phase voltage D: line-to-line voltage and zero
- 3
智慧职教: DC voltmeter can be used anywhere.
- 4
In previous simulation and on-site experiment, where is the voltage difference between the source voltage and the load voltage?