NC为()。
举一反三
- NC为没有使用的空脚
- 两端固定的阶梯杆如图所示,横截面面积A2=2A1,受轴向载荷P作用,假设A端受压力为NA,C端受拉力为NC,则( )。 [img=234x99]1803088ae38304e.png[/img] A: NA = -P/2, NC = P/2; B: NA = -P, NC = 0; C: NA = 2P/3, NC = P/3; D: NA = 0, NC = P;
- 对于0-1背包问题,用动态规划法的计算时间为() A: O(min{nc,2^n}) B: O(min{nc}) C: O(min{2^n}) D: O(min{nc,2n})
- 两端固定的阶梯杆如图所示,横截面面积A2=2A1,受轴向载荷P作用,两端的约束力为() A: NA=-P/2;NC=P/2 B: NA=-P;NC=0 C: NA=-2P/3;NC=P/3 D: NA=0;NC=P
- 1. Charges of 3.00 nC, –2.00 nC, –7.00 nC, and 1.00 nC are contained inside a rectangular box with length 1.00 m, width 2.00 m, and height 2.50 m. Outside the box are charges of 1.00 nC and 4.00 nC. What is the electric flux through the surface of the box?