A. To increase the voltage. B. To measure the current. C. To prevent overloading. D. To change the direction of the current. 相关知识点: 试题来源: 解析 C。解析:保险丝在电路中的主要作用是防止过载。选项 A,保险丝不能增加电压。选项 B,测量电流的是电流表等仪器。选项 D,保险丝不能改变电...
A long, vertical, metallic wire carries downward electric current. What is the direction of the magnetic field it creates at a point 2 cm horizontally east of the center of the wire? A. south B. north C. east D. west E. up
The current flows from region of high potential to low potential. The current is a scalar quantity.Answer and Explanation: Initially, when the current was discovered, it was supposed that positive particles move causing the current. So the direction was positive terminal...Become a member and un...
Electric current is themovementof electric charge.It’s not the charge itself. As a metaphor, you can think of a river. If a lot of water moves past a point in the river, it means the current is strong. If the water stands almost still, it means the current is weak. (And if ther...
当采用柴油机消防水泵时应符合下列规定：1 柴油机消防水泵应采用压缩式点火型柴油机;2 柴油机的额定功率应校核海拔高度和环境温度对柴油机功率的影响;3 柴油机消防水泵应具备连续工作的性能，试验运行时间不应小于24h;4 柴油机消防水泵的蓄电池应保证消防水泵随时自动启泵的要求;5 柴油机消防水泵的供油箱应根据火灾...
To the casual ob-server, dust seems to act in a totally random fashion, moving about chaotically without fixed direction. But in fact dust particles are much larger than water droplets and they finally fall. The cloud droplet of average size is only 1/2500 inch in diameter. It is so ...
What is the direction of the curve points returned by entirePath()? [See description for details] ajaatshatru Explorer , Oct 12, 2015 Copy link to clipboard Copied The entirePath() of a polygon returned these points. As clarified in a different ...
What is an ebb current? What is a geostrophic current? What is momentum flux? What is the unit of flow rate? What is a nominal current? What is a turbidity current? What are air currents? Toward which direction does a NW wind blow?
Electric current can be either direct or alternating. Direct current (DC) flows in the same direction at all points in time, although the instantaneous magnitude of the current might vary. In an alternating current (AC), the flow of charge carriers reverses direction periodically. The number of...
A circuit is closed (complete) when a switch is turned to the ON, or closed, position (see diagram at the top of this page). Current, like voltage, can be direct or alternating. Direct current (dc): Represented by the symbols or on a digital multimeter. Flows only in one direction....