The acceleration of a bus is given by a(t) =α*t, where α = 1.2 m/s^3. If the bus’s position at time t = 1.0 s is 6.0 m, what is its position at time t = 2.0 s()
A. 11.8 m
B. 9.5 m
C. 10 m
D. 12.7 m
E. 13.2 m
F. 14.1 m
查看答案
设有一条单侧电源10 kV配电线路,在最大运行方式下末端三相短路电流为880A,线路所装设TA变比为400/5。配电线路L等值阻抗为长度为15km 。试求电流速断保护定值一次值为()A ,可靠系数取为1
A. 1144
B. 1142
C. 1141
D. 1143
已知某线路最大负荷所对应的阻抗一次值为121.3W,相应功率因数角为30°,该线路阻抗角为75°。该线路所配置的距离保护III段,采用方向阻抗圆特性。整定阻抗二次值为()欧姆。(可靠系数取1.3,返回系数取1.1,自起动系数取2,电压互感器变比为1100,电流互感器变比为120。)
A. 6.54
B. 6.55
C. 6.52
D. 6
According to the regulatory of the Food and Drug Administration, Clostridium botulinum must be destroyed on sterilization, and is required()
A. D-values
B. 6D-values
C. 12D-values
D. 不知道