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据相关研究,经过40min完全黑暗后,人眼对光的敏感性达到最高点,比黑暗前增加25000倍,将数据25000用科学记数法表示为(    )


  • A.
  • B.
  • C.
  • D.
答案: B
本题解析:

【解析】

【分析】科学记数法的表示形式为a×10n的形式,其中1≤|a|<10,n为整数.确定n的值时,要看把原数变成a时,小数点移动了多少位,n的绝对值与小数点移动的位数相同.当原数绝对值大于或等于10时, n是正整数;当原数的绝对值小于1时,n是负整数.

【详解】解:将数据25000用科学记数法表示为2.5×104

故选:B.

【点睛】此题考查科学计数法,科学记数法的表示形式为a×10n的形式,其中1≤|a|<10,n为整数.


更新时间:2022-04-14 16:05
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