請問像的速度是多少?????

像既速度要視乎你點睇..
本身個像就係以y ms向住鏡尼行
但係如果係你望個像有幾快既話
因為你本身係向住塊鏡以y ms行,,然後再加上你個像以-y ms行
咁你就會望個像以 2y ms既速度向住你行..

如果有第3個人係塊鏡度望你個像有幾快,,佢先會睇到y ms 向住塊鏡行..

Strictly speaking, if a person is moving at velocity y m/s towards the mirror, his image is also moving at velocity of - y m/s towards the mirror (the -ve sign indicates that the direction of the image velocity is opposite to that of the person).
Hence, the velocity of his image relative to the person
= (-y - y) m/2 = -2y m/s

像既速度會係-y ms，即係同一速度但相反方向。因為平面鏡同實物既比例係1:1，即距離相同......時間也相同，所以速度會相同，至於方向相信唔洗解釋~


希望幫到你~^^

2009-06-14 12:51:57 補充：
問題係樓主只係問個像的實際速度，而唔係望到既速度，所以只係-y ms既速度。

-y ms^-1 ?