ÌâÄ¿ÄÚÈÝ

ÔÚ×ø±êÔ­µãµÄ²¨Ô´S²úÉúÒ»ÁÐÑØxÖáÕý·½Ïò´«²¥µÄ¼òг²¨£¬²¨ËÙv="400" m/s.ÒÑÖªt=0ʱ£¬²¨¸ÕºÃ´«²¥µ½x="30" m´¦£¬Èçͼ12-3-10Ëùʾ£¬ÔÚx="400" m´¦ÓÐÒ»½ÓÊÕÆ÷£¨Í¼ÖÐδ»­³ö£©£¬ÔòÏÂÁÐ˵·¨ÕýÈ·µÄÊÇ

ͼ12-3-10


  1. A.
    ²¨Ô´S¿ªÊ¼Õñ¶¯µÄ·½ÏòÑØyÖáÕý·½Ïò
  2. B.
    x="30" m´¦µÄÖʵãÔÚt="0.5" sÊ±Î»ÒÆ×î´ó
  3. C.
    x="20" m´¦µÄÖʵãµÄÕñ¶¯ÆµÂÊÊÇ40 Hz
  4. D.
    ½ÓÊÕÆ÷ÔÚt="1" sʱ²ÅÄܽÓÊÕµ½´Ë²¨
A
ÔÚt=0ʱ£¬²¨ÒÑÏòǰ´«²¥ÁË£¬¼´´«ÁË£¬´ËʱSµãÏòÏÂÕñ¶¯£¬ÔòÒÔǰ£¬²¨Ô´SÏòÉÏÕñ¶¯£¬AÕýÈ·.Óɲ¨µÄͼÏ󣬽áºÏÌâÖÐÊý¾Ý£¬Í¨¹ý¼ÆËãÖªB¡¢C¡¢D´í
Á·Ï°²áϵÁдð°¸
Ïà¹ØÌâÄ¿

Î¥·¨ºÍ²»Á¼ÐÅÏ¢¾Ù±¨µç»°£º027-86699610 ¾Ù±¨ÓÊÏ䣺58377363@163.com

¾«Ó¢¼Ò½ÌÍø