ÌâÄ¿ÄÚÈÝ
ÈçͼËùʾ£¬ÓÐÁ½ÌõƽÐеÄˮƽÖáÏßx1¡¢x2Ïà¾àΪd£¬ÔÚÉÏ·½Óд¹Ö±ÓÚÖ½ÃæÏòÍâµÄÔÈÇ¿´Å³¡¢ñ£¬´Å¸ÐӦǿ¶ÈµÄ´óСΪ2B£¬ÔÚx2Ï·½Óд¹Ö±ÓÚÖ½ÃæÏòÀïµÄÔÈÇ¿´Å³¡¢ò£¬´Å¸ÐӦǿ¶È´óСΪB£»ÔÚx1ºÍx2Ö®¼äÓÐÊúÖ±ÏòϵÄÔÈÇ¿µç³¡£¬µç³¡Ç¿¶ÈΪE£®Ò»ÖÊÁ¿Îªm£¬´øÕýµçºÉÁ¿ÎªqµÄ΢Á£´Óx1ÖáÉϵÄOµãÒÔËÙ¶Èv0£¬ÊúÖ±ÏòÉÏÉäÈëÔÈÇ¿´Å³¡¢ñÖУ¬Æäºó¸Ã΢Á£½«¶à´Î´©Ô½x1ºÍx2ÖᣬÈô΢Á£µÄÖØÁ¦²»¼Æ£¬µç³¡Ç¿¶ÈE Âú×㣺E=
£¬Çó£º
£¨1£©´ÓOµãÉäÈëºó£¬Î¢Á£µÚ2´Î¾¹ýx1ÖáʱÓëOµãµÄ¾àÀ룻
£¨2£©Î¢Á£´ÓOµãÉäÈëºóµ½µÚ4´Îͨ¹ýx1ÖáÏßËùÓõÄʱ¼ä£®![¾«Ó¢¼Ò½ÌÍø](http://thumb.1010pic.com/pic2/upload/papers/20130925/201309251754415454232.png)
3m
| ||
2qd |
£¨1£©´ÓOµãÉäÈëºó£¬Î¢Á£µÚ2´Î¾¹ýx1ÖáʱÓëOµãµÄ¾àÀ룻
£¨2£©Î¢Á£´ÓOµãÉäÈëºóµ½µÚ4´Îͨ¹ýx1ÖáÏßËùÓõÄʱ¼ä£®
![¾«Ó¢¼Ò½ÌÍø](http://thumb.1010pic.com/pic2/upload/papers/20130925/201309251754415454232.png)
£¨1£©ÔÚÔÈÇ¿´Å³¡¢ñÖУ¬ÂåÂ××ÈÁ¦ÌṩÏòÐÄÁ¦µÃ£ºqv0?2B=
ËùÒÔ£ºr1=
ÔÚÔÈÇ¿µç³¡ÖÐ v2-
=2
d
ÒòΪE=
ËùÒÔv=2v0
ÔÚÔÈÇ¿´Å³¡¢òÖÐ r2=
ËùÒÔ΢Á£µÚ¶þ´Î¾¹ýx1ÖáʱÓëOµãµÄ¾àÀëΪx=2r1+2r2=
£¨2£©Î¢Á£Ã¿´ÎÏòÏ´©Ô½µç³¡×÷¼ÓËÙÔ˶¯£¬´Óv0µ½2 v0£¬¶øÏòÉÏ´©Ô½µç³¡×÷¼õËÙÔ˶¯£¬ÓÖ´Ó2v0µ½ v0£¬ËùÓõÄʱ¼ä¾ùΪt1
ÓÉd=
t1£¬µÃt1=
ÔÚÔÈÇ¿´Å³¡¢ñÖÐT1=
ÔÚÔÈÇ¿´Å³¡¢òÖÐT2=
µÚ4´Î¾¹ýx1ÖáµÄʱ¼ä£ºt4=T1+T2+4t1=
+
´ð£º£¨1£©´ÓOµãÉäÈëºó£¬Î¢Á£µÚ2´Î¾¹ýx1ÖáʱÓëOµãµÄ¾àÀëÊÇ
£»
£¨2£©Î¢Á£´ÓOµãÉäÈëºóµ½µÚ4´Îͨ¹ýx1ÖáÏßËùÓõÄʱ¼ä
+
£®
m
| ||
r1 |
ËùÒÔ£ºr1=
mv0 |
2qB |
ÔÚÔÈÇ¿µç³¡ÖÐ v2-
v | 20 |
qE |
m |
ÒòΪE=
3m
| ||
2qd |
ÔÚÔÈÇ¿´Å³¡¢òÖÐ r2=
2mv0 |
qB |
ËùÒÔ΢Á£µÚ¶þ´Î¾¹ýx1ÖáʱÓëOµãµÄ¾àÀëΪx=2r1+2r2=
5mv0 |
qB |
£¨2£©Î¢Á£Ã¿´ÎÏòÏ´©Ô½µç³¡×÷¼ÓËÙÔ˶¯£¬´Óv0µ½2 v0£¬¶øÏòÉÏ´©Ô½µç³¡×÷¼õËÙÔ˶¯£¬ÓÖ´Ó2v0µ½ v0£¬ËùÓõÄʱ¼ä¾ùΪt1
ÓÉd=
v0+v |
2 |
2d |
3v0 |
ÔÚÔÈÇ¿´Å³¡¢ñÖÐT1=
2¦Ðm |
2qB |
ÔÚÔÈÇ¿´Å³¡¢òÖÐT2=
2¦Ðm |
qB |
µÚ4´Î¾¹ýx1ÖáµÄʱ¼ä£ºt4=T1+T2+4t1=
3¦Ðm |
qB |
8d |
3v0 |
´ð£º£¨1£©´ÓOµãÉäÈëºó£¬Î¢Á£µÚ2´Î¾¹ýx1ÖáʱÓëOµãµÄ¾àÀëÊÇ
5mv0 |
qB |
£¨2£©Î¢Á£´ÓOµãÉäÈëºóµ½µÚ4´Îͨ¹ýx1ÖáÏßËùÓõÄʱ¼ä
3¦Ðm |
qB |
8d |
3v0 |
![](http://thumb2018.1010pic.com/images/loading.gif)
Á·Ï°²áϵÁдð°¸
Ïà¹ØÌâÄ¿