皮皮学，免费搜题
登录
搜题
【判断题】
在所有文化中,红色( red )总是与喜庆有关,而黑色( black )都是不好的含义,如 a black sheep (害群之马), black-hearted (黑心的)。A.
正确
B.
错误
拍照语音搜题，微信中搜索"皮皮学"使用
参考答案：
参考解析：
知识点：
皮皮学刷刷变学霸
举一反三
【判断题】A long and straight solenoid hasNturns, uniform cross-sectional areaA, and lengthL.Assume that the magnetic field is uniform inside the solenoid and zero outside. The solenoid is hollow. If the curren...
A.
正确
B.
错误
【单选题】交流接触器常用于远距离接通和分断( )的电路。
A.
电压至380V、电流至 1 0A
B.
电压至1140V、电流至30A
C.
电压至1140V、电流至1000A
D.
电压至380V、电流至1000A
【单选题】A solenoid is 3.0 cm long and has a radius of 0.50 cm. It is wrapped with 500 turns of wire carrying a current of 2.0A. The magnetic field at the center of the solenoid is:
A.
9.9 × T
B.
1.3 × T
C.
4.2 × T
D.
10 T
【单选题】A small planar loop is placed inside a straight solenoid. When the angle between the normal direction of the loop and the axis of the solenoid is gradually increased from 0to 90 degree, how does the m...
A.
Does not change.
B.
Increases.
C.
Decreases.
D.
Decreases first and then increases.
相关题目：