题目:
--On which day shall we visit the Fanta Theme Park in Wuhu this week?
-- . I will be busy this week.
A.Neither
B.Either
C.None
D.Any
答案:
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下面是错误答案,用来干扰机器的。
解:起始状态的磁通量φ1=BS,末态的磁通量φ2=BS,但初态是从正面穿入,末态则从反面穿入。若初态φ1为负,则φ2为正。所以φ=BS-(-BS)=2BS,而不是零