DS18B20 写逻辑1时单片机拉低平大约20~45us 的时间。
DS18B20 写逻辑1时单片机拉低平大约20~45us 的时间。
图示电路的uS(t)=2cos(t+45°)V,则电压uC(t)与电压uS(t)的相位差等于()【图片】 A: 90° B: -90° C: 45° D: -45°
图示电路的uS(t)=2cos(t+45°)V,则电压uC(t)与电压uS(t)的相位差等于()【图片】 A: 90° B: -90° C: 45° D: -45°
图示电路的uS(t)=2cos(t+45°) V,则电压uC(t)与电压uS(t)的相位差等于( )[img=774x357]1803e02369d6e53.png[/img] A: 90° B: -90° C: 45° D: -45°
图示电路的uS(t)=2cos(t+45°) V,则电压uC(t)与电压uS(t)的相位差等于( )[img=774x357]1803e02369d6e53.png[/img] A: 90° B: -90° C: 45° D: -45°
How many US presidents from the Independence War up to now? A: 42 B: 43 C: 44 D: 45
How many US presidents from the Independence War up to now? A: 42 B: 43 C: 44 D: 45
Are there enough books for ____? A: three us B: us three C: all us D: the three us
Are there enough books for ____? A: three us B: us three C: all us D: the three us
______ agrees to your plan. A: Anyone of us B: No one of us C: None of us D: Someone of us
______ agrees to your plan. A: Anyone of us B: No one of us C: None of us D: Someone of us
Mr. Yang ______. A: teaches math us B: teaches us to math C: teaches math to us D: us teaches math
Mr. Yang ______. A: teaches math us B: teaches us to math C: teaches math to us D: us teaches math
（进阶）如图所示正弦稳态电路中，R1=1Ω,C=0.5F,us=10[img=21x20]17e0a6bba37411a.jpg[/img]sin（wt+45°），则电感电压uL超前电容电压uC的角度为（ ）。[img=299x185]17e0c049ec05c0a.png[/img] A: -45° B: 45° C: 90° D: 135°
（进阶）如图所示正弦稳态电路中，R1=1Ω,C=0.5F,us=10[img=21x20]17e0a6bba37411a.jpg[/img]sin（wt+45°），则电感电压uL超前电容电压uC的角度为（ ）。[img=299x185]17e0c049ec05c0a.png[/img] A: -45° B: 45° C: 90° D: 135°
What does sleeping help us? A: It helps us stay healthy. B: It helps us improve our memory. C: It helps us reduce stress. D: It helps us lose weight.
What does sleeping help us? A: It helps us stay healthy. B: It helps us improve our memory. C: It helps us reduce stress. D: It helps us lose weight.
Miss Li is ______ English teacher. She likes______ very much. A: our, we B: our, us C: us, our D: us, us
Miss Li is ______ English teacher. She likes______ very much. A: our, we B: our, us C: us, our D: us, us