ÌâÄ¿ÄÚÈÝ
20£®ÈçͼËùʾ£¬ÔÚÇã½ÇΪ¦ÈµÄ¹â»¬Ð±ÃæÉÏÓÐÁ½¸öÓÃÇáÖʵ¯»ÉÏàÁ¬½ÓµÄÎï¿éA¡¢B£®ËüÃǵÄÖÊÁ¿¾ùΪm£¬µ¯»ÉµÄ¾¢¶ÈϵÊýΪk£¬CΪһ¹Ì¶¨µ²°å£¬ÏµÍ³´¦ÓÚ¾²Ö¹×´Ì¬£®ÏÖ¶ÔÎï¿éAÊ©¼ÓÒ»ÑØбÃæÏòϵÄ˲ʱ³åÁ¿£¬Ê¹Îï¿éAÔÚбÃæÉÏÔ˶¯£¬µ±Îï¿éB¸ÕÒªÀ뿪Cʱ£¬Îï¿éAµÄËÙ¶ÈΪv£¬Ô˶¯µÄλÒÆ´óСΪd£®ÔòÔÚ´ÓÊ©¼Ó³åÁ¿¿ªÊ¼µÄÕû¸ö¹ý³ÌÖУ¨¡¡¡¡£©A£® | µ¯»É¶ÔÎï¿éA×ö¹¦ÎªÁã | |
B£® | A¡¢BÓ뵯»É×é³ÉµÄϵͳ»úеÄÜÊغã | |
C£® | Îï¿éA¡¢BµÄÖÊÁ¿Âú×ã2mgsin¦È=kd | |
D£® | µ¯»ÉµÄµ¯ÐÔÊÆÄܵļõСÁ¿Îªmdgsin¦È+$\frac{1}{2}$mv2 |
·ÖÎö ¸ù¾ÝÐαäÁ¿·ÖÎöµ¯»É¶ÔÎï¿éA×öµÄ¹¦£®¸ù¾Ý»úеÄÜÊغãÌõ¼þ£ºÖ»ÓÐÖØÁ¦»òµ¯Á¦×ö¹¦·ÖÎöϵͳµÄ»úеÄÜÊÇ·ñÊغ㣮µ±Îï¿éB¸ÕÒªÀ뿪Cʱ£¬µ¯»ÉµÄµ¯Á¦µÈÓÚBµÄÖØÁ¦ÑØбÃæÏòϵķÖÁ¦£®¸ù¾Ý¹¦ÄܹØϵ·ÖÎöµ¯»ÉµÄµ¯ÐÔÊÆÄܵļõСÁ¿£®
½â´ð ½â£ºA¡¢ÏµÍ³´¦ÓÚ¾²Ö¹×´Ì¬Ê±£¬µ¯»ÉµÄѹËõÁ¿Îª x1=$\frac{mgsin¦È}{k}$£®µ±Îï¿éB¸ÕÒªÀ뿪Cʱ£¬µ¯»ÉµÄÉ쳤Á¿Îª x2=$\frac{mgsin¦È}{k}$£¬Ôòx1=x2£¬¿ÉÖªµ¯»É¶ÔÎï¿éA×ö¹¦ÎªÁ㣮¹ÊAÕýÈ·£®
B¡¢¶ÔÓÚA¡¢BÓ뵯»É×é³ÉµÄϵͳ£¬ÓÉÓÚÊ©¼ÓÁ˳åÁ¿£¬ËùÒÔÍâÁ¦¶Ôϵͳ×ö¹¦£¬ÔòϵͳµÄ»úеÄܲ»Êغ㣬¹ÊB´íÎó£®
C¡¢¸ù¾Ý¼¸ºÎ¹ØϵµÃ£ºd=x1+x2£¬ÁªÁ¢x1=$\frac{mgsin¦È}{k}$£¬x2=$\frac{mgsin¦È}{k}$£¬µÃ 2mgsin¦È=kd£¬¹ÊCÕýÈ·£®
D¡¢ÓÉÉÏ·ÖÎöÖª£¬µ¯»É¶ÔÎï¿éA×ö¹¦ÎªÁ㣬Ôòµ¯»ÉµÄµ¯ÐÔÊÆÄܵļõСÁ¿Îª0£¬¹ÊD´íÎó£®
¹ÊÑ¡£ºAC
µãÆÀ ¶ÔÓÚº¬Óе¯»ÉµÄÎÊÌ⣬ÍùÍùÒªÑо¿µ¯»ÉµÄ״̬£¬·ÖÎöÎï¿éµÄλÒÆÓ뵯»ÉѹËõÁ¿ºÍÉ쳤Á¿µÄ¹ØϵÊdz£ÓÃ˼·£®
A£® | v1=v2 | |
B£® | W1=W2 | |
C£® | СÇòµÚÒ»´ÎÔÚBµã¶Ô¹ìµÀµÄѹÁ¦Ð¡ÓÚµÚ¶þ´ÎÔÚBµã¶Ô¹ìµÀµÄѹÁ¦ | |
D£® | СÇòµÚÒ»´Î¾¹ýÔ²»¡ACµÄ¹ý³ÌÖп˷þĦ²ÁÁ¦×öµÄ¹¦Îª$\frac{1}{2}$W1 |
A£® | ÂÖ´¬ÔÚ¿¿°¶¹ý³ÌÖпÉÄÜ×öÔÈËÙÔ˶¯ | |
B£® | ´ËʱÆû³µµÄËÙ¶ÈΪv³µ=$\frac{v}{cos¦È}$ | |
C£® | ´ËʱÉþµÄÀÁ¦T=$\frac{P}{vcos¦È}$-ma-f | |
D£® | ´ËʱÉþµÄÀÁ¦¶Ô´¬×ö¹¦µÄ¹¦ÂÊPT=P-£¨f+ma£©vcos¦È |
A£® | ¦ÁÁ£×ӺͦÂÁ£×ÓµÄÔ˶¯¹ì¼£·Ö±ðΪͼÖеÄb¡¢a | |
B£® | ´Å³¡µÄ·½ÏòÒ»¶¨´¹Ö±Ö½ÃæÏòÀï | |
C£® | c±íʾ¦ÂÁ£×ÓµÄÔ˶¯¹ì¼£ | |
D£® | ¦ÁÁ£×ӺͦÂÁ£×ÓµÄÔ˶¯¹ì¼£µÄ°ë¾¶Ö®±ÈΪ1£º2 |
A£® | ¿ÉÄÜ×öÔȱäËÙÖ±ÏßÔ˶¯£¬¼ÓËٶȴóС¿ÉÄܵÈÓÚ1.5m/s2 | |
B£® | ¿ÉÄÜ×öÀàƽÅ×Ô˶¯£¬¼ÓËٶȴóС¿ÉÄܵÈÓÚ12m/s2 | |
C£® | ¿ÉÄÜ×öÔÈËÙÔ²ÖÜÔ˶¯£¬ÏòÐļÓËٶȴóС¿ÉÄܵÈÓÚ3m/s2 | |
D£® | Ò»¶¨×öÔȱäËÙÔ˶¯£¬¼ÓËٶȴóС¿ÉÄܵÈÓÚ6m/s2 |
A£® | ¼×´øÕýµçºÉ£¬ÒÒ´ø¸ºµçºÉ | |
B£® | ÂåÂ××ÈÁ¦¶Ô¼×ÒÒ²»×öÕý¹¦ | |
C£® | ¼×µÄËÙÂÊ´óÓÚÒÒµÄËÙÂÊ | |
D£® | ¼×Ôڴų¡ÖÐÔ˶¯µÄʱ¼ä´óÓÚÒÒÔڴų¡ÖÐÔ˶¯µÄʱ¼ä |