Em | ||
|
2 |
E有 |
R+r |
2 |
2π |
ω |
π |
2 |
. |
I |
N△Φ |
R+r |
NBSsinθ |
R+r |
E2有 |
R+r |
A.使线圈匝数增加一倍 |
B.使线圈面积增加一倍 |
C.使线圈匝数减少一半 |
D.使磁感应强度的变化率增大一倍 |
A.5
| B.5A | C.3.5
| D.3.5A |
A.电路中交变电流的频率为0.25Hz | ||
B.用交流电流表测得通过电阻的电流为
| ||
C.电阻消耗的电功率为2.5W | ||
D.用交流电压表测得电阻两端的电压是5V |
A.220V | B.110V | C.110
| D.55
|
© 2017-2019 超级试练试题库,All Rights Reserved.