如何定义磁通量?
参考答案:
所谓磁通,就是磁感应强度B和与其垂直的面积S的乘积;符号用Φ其单位是韦伯(Wb);磁通量是标量,没有方向只有大小。
—Are these Chinese books?
—Yes,_______. [ ]
A. they are
B. these are
C. they're
D. they are right
主动脉瓣关闭不全则会有
A.主动脉瓣区收缩期喷射样杂音B.主动脉瓣副区舒张期叹息样杂音C.胸骨左缘第三、四肋间响亮粗糙吹风样杂音D.心尖区收缩期吹风样杂音E.心尖区舒张期隆隆样杂音