A、试用电源等效变换法求图示电路中的电流I。
<img src="https://img.ppkao.com/2018-09/lina/2018090210415085719.jpg" />
A、在牛顿-柯特斯求积公式:<img src="https://img.ppkao.com/2019-05/wanxiaokui/2019051614474078173.jpg" />中,当系数<img src="https://img.ppkao.com/2019-05/wanxiaokui/2019051614472994714.jpg" />是负值时,公式的稳定性不能保证,所以实际应用中,当()时的牛顿-柯特斯求积公式不使用。
A、A.<img src="https://img.ppkao.com/2017-10/wangyu/2017102215551029653.jpg"/>
B.<img src="https://img.ppkao.com/2017-10/wangyu/2017102215551448416.jpg"/>
C.18A
D.12A
A、用结点电压法求如图所示电路的U1和I。
<img src="https://img.ppkao.com/2019-05/leiyawen/2019051609333393120.jpg" />
A、如图所示,在由无限大平面和突起的半球构成的接地导体上方距离平面为d处有一个点电荷q0。利用镜像法求z轴上z>a各点的电位分布。
<img src="https://img.ppkao.com/2019-04/wuacheng/201904091656085662.jpg" />
A、A.<img src="https://img.ppkao.com/2017-10/wangjinchen/2017101309154866509.jpg" />低电平,<img src="https://img.ppkao.com/2017-10/wangjinchen/2017101309155838776.jpg" />三态,<img src="https://img.ppkao.com/2017-10/wangjinchen/2017101309155342124.jpg" />低电平
B.<img src="https://img.ppkao.com/2017-10/wangjinchen/2017101309154866509.jpg" />三态,<img src="https://img.ppkao.com/2017-10/wangjinchen/2017101309155838776.jpg" />低电平,<img src="https://img.ppkao.com/2017-10/wangjinchen/2017101309155342124.jpg" />高电平
C.<img src="https://img.ppkao.com/2017-10/wangjinchen/2017101309154866509.jpg" />低电平,<img src="https://img.ppkao.com/2017-10/wangjinchen/2017101309155838776.jpg" />高电平,<img src="https://img.ppkao.com/2017-10/wangjinchen/2017101309155342124.jpg" />高电平
D.<img src="https://img.ppkao.com/2017-10/wangjinchen/2017101309154866509.jpg" />高电平,<img src="https://img.ppkao.com/2017-10/wangjinchen/2017101309155838776.jpg" />低电平,<img src="https://img.ppkao.com/2017-10/wangjinchen/2017101309155342124.jpg" />高电平
A、A.<img src="https://img.ppkao.com/2017-12/xieqiushi/2017120716370781231.jpg" />不变,<img src="https://img.ppkao.com/2017-12/xieqiushi/2017120716372262539.jpg" />增大
B.<img src="https://img.ppkao.com/2017-12/xieqiushi/2017120716370781231.jpg" />减小,<img src="https://img.ppkao.com/2017-12/xieqiushi/2017120716372262539.jpg" />不变
C.<img src="https://img.ppkao.com/2017-12/xieqiushi/2017120716370781231.jpg" />减小,<img src="https://img.ppkao.com/2017-12/xieqiushi/2017120716372262539.jpg" />增大
D.<img src="https://img.ppkao.com/2017-12/xieqiushi/2017120716370781231.jpg" />增大,<img src="https://img.ppkao.com/2017-12/xieqiushi/2017120716372262539.jpg" />减小