ÌâÄ¿ÄÚÈÝ
17£®ÈçͼËùʾ£¬Ò»¸öÖÊÁ¿m=0.1gµÄС»¬¿é£¨¿ÉÊÓΪÖʵ㣩£¬´øÓÐq=-5¡Á10-4CµÄµçºÉÁ¿£¬·ÅÖÃÔÚÇã½Ç¦Á=30¡ãµÄ¹Ì¶¨¹â»¬¾øԵбÃæÉÏ£®Ð±ÃæÖÃÓÚB=0.5TµÄÔÈÇ¿´Å³¡ÖУ¬´Å³¡·½Ïò´¹Ö±Ö½ÃæÏòÀС»¬¿éÓɾ²Ö¹¿ªÊ¼ÑØбÃ滬Ï£¬ÈôбÃæ×ã¹»³¤£¬Ð¡»¬¿é»¬ÖÁijһλÖÃʱ£¬½«ÒªÀ뿪бÃ森gÈ¡10m/s2£®Ç󣺣¨1£©Ð¡»¬¿éÀ뿪бÃæµÄ˲ʱËٶȶà´ó£»
£¨2£©ÒªÂú×㻬¿éÏ»¬¹ý³ÌÖÐÄÜÀ뿪бÃ棬¸ÃбÃæµÄ³¤¶ÈÖÁÉÙ¶àÉÙ£®
·ÖÎö £¨1£©´øµç»¬¿éÔÚ»¬ÖÁijһλÖÃʱ£¬ÓÉÓÚÔÚÂåÂ××ÈÁ¦µÄ×÷ÓÃÏ£¬ÒªÀ뿪бÃ森¸ù¾Ý´Å³¡·½Ïò½áºÏ×óÊÖ¶¨Ôò¿ÉµÃ´øµçÁ£×ӵĵçÐÔ£®Óɹ⻬бÃ棬ËùÒÔС»¬¿éÔÚûÓÐÀ뿪бÃæ֮ǰһֱ×öÔȼÓËÙÖ±ÏßÔ˶¯£®½èÖúÓÚÂåÂ××ÈÁ¦¹«Ê½¿ÉÇó³öÇ¡ºÃÀ뿪ʱµÄËٶȴóС£¬
£¨2£©ÓÉÔ˶¯Ñ§¹«Ê½À´Ëã³öÔȼÓËÙÔ˶¯µÄʱ¼ä£®ÓÉλÒÆÓëʱ¼ä¹Øϵ¿ÉÇó³öλÒÆ´óС£®
½â´ð ½â£º£¨1£©ÓÉÌâÒâ¿ÉÖª£ºÐ¡»¬¿éÊܵ½µÄÂåÂ××ÈÁ¦´¹Ö±Ð±ÃæÏòÉÏ£®¸ù¾Ý×óÊÖ¶¨Ôò¿ÉµÃ£ºÐ¡»¬¿é´ø¸ºµç£®
ÓÉÌâÒ⣺µ±»¬¿éÀ뿪бÃæʱ£¬ÂåÂ××ÈÁ¦£ºBqv=mgcos¦Á£¬
Ôòv=$\frac{mgcos¦Á}{qB}=\frac{0.1¡Á10¡Ácos30¡ã}{5¡Á1{0}^{-4}¡Á0.5}m/s=2\sqrt{3}$m/s
£¨2£©ÓÖÒòΪÀ뿪֮ǰ£¬Ò»Ö±×öÔȼÓËÙÖ±ÏßÔ˶¯
ÔòÓУºmgsina=ma£¬
¼´a=gsina=5m/s2£¬
ÓÉv2=2axµÃ£º$x=\frac{{v}^{2}}{2gsin¦Á}=1.2$m
´ð£º£¨1£©Ð¡»¬¿éÀ뿪бÃæʱµÄ˲ʱËÙ¶ÈÊÇ$2\sqrt{3}$m/s£»£¨2£©¸ÃбÃæµÄ³¤¶ÈÖÁÉÙ³¤1.2m
µãÆÀ ±¾ÌâÍ»ÆÆ¿ÚÊÇ´ÓС»¬¿é¸Õ´ÓбÃæÀ뿪ʱ£¬´Ó¶øÈ·¶¨ÂåÂ××ÈÁ¦µÄ´óС£¬½ø¶øµÃ³ö¸ÕÀ뿪ʱµÄËٶȴóС£¬ÓÉÓÚûÓÐÀ뿪֮ǰ×öÔȼÓËÙÖ±ÏßÔ˶¯£¬ËùÒÔÓÉÔ˶¯ÓëÁ¦Ñ§¿É½â³öÔ˶¯µÄʱ¼ä¼°Î»ÒÆ£®
A£® | v1£¾v2 | B£® | v1£¼v2 | C£® | v1=v2 | D£® | ÎÞ·¨È·¶¨ |
A£® | ͨ¹ýabcdƽÃæµÄ´ÅͨÁ¿´óСΪL2•B | |
B£® | ͨ¹ýdcfeƽÃæµÄ´ÅͨÁ¿´óСΪ$\frac{\sqrt{2}}{2}$L2•B | |
C£® | ͨ¹ýabfeƽÃæµÄ´ÅͨÁ¿´óСΪL2•B | |
D£® | ͨ¹ýÕû¸öÈýÀâÖùµÄ´ÅͨÁ¿Îª$\frac{\sqrt{2}}{2}$L2•B |
A£® | vc£ºvd=2£º1 | B£® | vc£ºvd=$\sqrt{2}$£º1 | C£® | tc£ºtd=1£º$\sqrt{2}$ | D£® | tc£ºtd=1£º2 |
A£® | »¬¶¯±ä×èÆ÷RµÄ×èÖµ±äС | B£® | µÆÅÝL±äÁÁ | ||
C£® | µçÔ´ÏûºÄµÄ×ܹ¦ÂÊÔö´ó | D£® | µçÈÝÆ÷CµÄµçºÉÁ¿Ôö´ó |
A£® | СÇòÔ˶¯µÄ¹ì¼£ÊÇÒ»ÌõÅ×ÎïÏß | B£® | ÂåÂ××ÈÁ¦¶ÔСÇò×öÕý¹¦ | ||
C£® | СÇò´ø¸ºµç | D£® | ά³ÖÊÔ¹ÜÔÈËÙÔ˶¯µÄÀÁ¦FÓ¦¼õС |
A£® | $\frac{1}{2¦Ð}$ $\sqrt{\frac{g}{h}}$ | B£® | ¦Ð$\sqrt{gh}$ | C£® | $\frac{1}{2¦Ð}$ $\sqrt{\frac{g}{l}}$ | D£® | 2¦Ð $\sqrt{\frac{l}{g}}$ |