A、求图所示电路在开关S打开和闭合两种情况下的等效电阻R<sub>absub>。r /> src="https://img.ppkao.com/2019-04/wangxuan/2019042616331161571.jpg" />
A、求图所示电路在开关S打开和闭合两种情况下的等效电阻R<sub>absub>。r /> src="https://img.ppkao.com/2019-04/wangxuan/2019042616331161571.jpg" />
A、R<sub>1sub>烧坏,R<sub>2sub>不会烧坏 B、R<sub>1sub>、R<sub>2sub>均烧坏 C、R<sub>1sub>未烧坏,R<sub>2sub>烧坏 D、R<sub>1sub>、R<sub>2sub>均未烧坏
A、如题68图所示电路,运算放大器为理想运算放大器,已知U<sub>i1sub>=2V,U<sub>i2sub>=4V,R<sub>1sub>=194;R<sub>5sub>=10kΩ,R<sub>2sub>=20194;kΩ,R<sub>3sub>=194;R<sub>4sub>=5194;kΩ。求:r /> src="https://img.ppkao.com/2018-09/tianmin/2018090510023683894.jpg" />
A、如题68图所示电路,运算放大器为理想运算放大器,已知U<sub>i1sub>=2V,U<sub>i2sub>=4V,R<sub>1sub>=194;R<sub>5sub>=10kΩ,R<sub>2sub>=20194;kΩ,R<sub>3sub>=194;R<sub>4sub>=5194;kΩ。求:r /> src="https://img.ppkao.com/2018-09/tianmin/2018090510023683894.jpg" />
A、R<sub>1sub>烧坏,R<sub>2sub>不会烧坏 B、R<sub>1sub>,R<sub>2sub>均烧坏 C、R<sub>1sub>未烧坏,R<sub>2sub>烧坏 D、R<sub>1sub>,R<sub>2sub>均未烧坏
A、如图所示电路中,u<sub>Ssub>=10sin314tV,R<sub>1sub>=2Ω,R<sub>2sub>=1Ω,L=637mH,C=637μF,求电流i<sub>1sub>,i<sub>2sub>和电压u<sub>csub>。r /> src="https://img.ppkao.com/2018-09/tangxueping/2018092818010827576.jpg" />
A、如图所示为电桥电路,已知R<sub>1sub>=1Ω、R<sub>2sub>=2Ω、R<sub>3sub>=2Ω、R<sub>4sub>=4Ω、R<sub>5sub>=5Ω,试求等效电阻R<sub>absub>。r /> src="https://img.ppkao.com/2018-05/tangxueping/2018051015543465216.jpg" />