The exact phase angle f of the factor is, . At zero frequency, the phase angle is 90°. At the corner frequency, the phase angle is,
A.
正确
B.
错误
拍照语音搜题,微信中搜索"皮皮学"使用
参考答案:
参考解析:
知识点:
皮皮学刷刷变学霸
举一反三
【单选题】Despite a very strong wind, a tennis player manages to hit a tennis ball with her racquet so that the ball passes over the net and lands in her opponent’s court. Consider the following forces: A. a do...
【单选题】Despite the approach of winter, oil prices to industrial customers are exceptionally low this year and likely to remain so. Therefore, unless the winter is especially severe, the price of natural gas ...
A.
Long-term weather forecasts predict a mild winter.
B.
The industrial users who consume most natural gas can quickly and cheaply switch to using oil instead.
C.
The largest sources of supply for both oil and natural gas are in subtropical regions unlikely to be affected by winter weather.
D.
The fuel requirements of industrial users of natural gas are not seriously affected by the weather.
E.
Oil distribution is more likely to be affected by severe winter weather than is the distribution of natural gas.