我怎么认为:如果M是波源，P点怎么看都是振动了四分之三T。为什么选C，我理解错了吗?求大神指导，3 急问高二物理题
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题目已经明确，波形是经过一个周期T的
根据波的传播的特点，若M是波源此时N开始振动，振动方向向上，P已经振动了T/4
若N是波源此时M开始振动，振动方向向下 P已经振动了3T/4
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绛旓細鐢卞浘璇诲嚭锛屾娉㈢殑娉㈤暱涓何=1m锛孫P璺濈x=10.25m=1014位锛屽綋姝ゆ尝鍒拌揪P鐐鏃讹紝澶勪簬鍘熺偣鐨凮澶勭殑璐ㄧ偣鎸姩浜10.25鍛ㄦ湡锛庡垯娉㈠埌杈綪鐐规椂锛孫鐐归氳繃鐨勮矾绋嬩负 S=10.25脳4A=10.25脳4脳2cm=82cm锛屽埌杈炬尝璋蜂綅缃紝浣嶇Щ涓 x=-2cm锛庢晠閫夛細C
绛旓細宸茬煡S1娉㈡簮鐩镐綅涓2蟺t+蟺/2锛屽垯P鐐鐩镐綅涓2蟺t+蟺/2-4蟺 璁維2鐩镐綅涓2蟺t+蠁锛屽垯P鐐圭浉浣嶄负2蟺t+蟺/2-4.4蟺 涓ゅ垪娉㈠湪P鐐瑰彂鐢熺浉娑堝共娑夛紝鐩镐綅宸负(2k+1)蟺 鍒欐湁锛2蟺t+蟺/2-4蟺锛-锛2蟺t+蠁-4.4蟺锛=(2k+1)蟺 褰搆=0鏃讹紝瑙ｅ緱蠁=-0.1蟺 鎵浠ワ紝2Acos(2蟺t-0.1蟺锛...
