ÌâÄ¿ÄÚÈÝ
4£®Ò»Áмòгºá²¨ÑØxÖáÕý·½Ïò´«²¥£¬t=0ʱ¿Ì²¨ÐÎͼÈçͼÖеÄʵÏßËùʾ£¬´Ëʱ²¨¸ÕºÃ´«µ½Pµã£¬t=0.6sʱ¿Ì£¬ÕâÁв¨¸ÕºÃ´«µ½Qµã£¬²¨ÐÎÈçͼÖеÄÐéÏßËùʾ£¬a¡¢b¡¢c¡¢P¡¢QÊǽéÖÊÖеÄÖʵ㣬ÔòÒÔÏÂ˵·¨ÕýÈ·µÄÊÇ£¨¡¡¡¡£©A£® | ÕâÁв¨µÄ²¨ËÙΪ16.7 m/s | |
B£® | ÕâÁв¨µÄÖÜÆÚΪ0.8 s | |
C£® | ÖʵãcÔÚÕâ¶Îʱ¼äÄÚͨ¹ýµÄ·³ÌÒ»¶¨µÈÓÚ30 cm | |
D£® | ´Ót=0ʱ¿Ì¿ªÊ¼¼Æʱ£¬ÖʵãaµÚÒ»´Îµ½´ïƽºâλÖÃʱ£¬Ç¡ºÃÊÇ$\frac{1}{3}$sÕâ¸öʱ¿Ì |
·ÖÎö ÓÉÌâ¶Á³öPQ¼äµÄ¾àÀë¡÷x£¬ÓÉv=$\frac{¡÷x}{¡÷t}$Çó³ö²¨ËÙ£»¶Á³ö²¨³¤£¬Óɹ«Ê½v=$\frac{¦Ë}{T}$ÇóÖÜÆÚ£®¸ù¾Ýʱ¼äÓëÖÜÆڵĹØϵÇóÖʵãcͨ¹ýµÄ·³Ì£®¸ù¾Ý²¨ÐεÄƽÒÆ·¨ÇóÖʵãaµÚÒ»´Îµ½´ïƽºâλÖõÄʱ¼ä£®
½â´ð ½â£ºA¡¢ÓÉÌâͼ֪£¬PQ¼äµÄ¾àÀë¡÷x=90m-60m=30m£¬Ôò²¨ËÙΪ v=$\frac{¡÷x}{¡÷t}$=$\frac{30}{0.6}$=50m/s£¬¹ÊA´íÎó
B¡¢²¨³¤Îª ¦Ë=40m£¬ÔòÕâÁв¨µÄÖÜÆÚΪ T=$\frac{¦Ë}{v}$=$\frac{40}{50}$s=0.8s£¬¹ÊBÕýÈ·£®
C¡¢²¨Ðδ«²¥µ½cλÖõÄʱ¼ä t1=$\frac{x}{v}$=$\frac{10}{50}$s=0.2s£¬ÔòÖª0.2sºóÖʵãc¿ªÊ¼Õñ¶¯£¬ÔÚ0.4sÄڵķ³Ì s=2A=20cm£®¹ÊC´íÎó£®
D¡¢ÖʵãaµÄÕñ¶¯·½³ÌΪ ya=Asin£¨$\frac{2¦Ð}{T}$t+$\frac{¦Ð}{6}$£©cm=10sin£¨2.5t+$\frac{¦Ð}{6}$£©cm£¬µ±t=$\frac{1}{3}$s£¬´úÈëµÃ£ºya=0£¬ÔòÖª£¬´Ót=0ʱ¿Ì¿ªÊ¼¼Æʱ£¬ÖʵãaµÚÒ»´Îµ½´ïƽºâλÖÃʱ£¬Ç¡ºÃÊÇ$\frac{1}{3}$sÕâ¸öʱ¿Ì£®¹ÊDÕýÈ·£®
¹ÊÑ¡£ºBD
µãÆÀ ±¾ÌâµÄ¹Ø¼üÒªÃ÷È·²¨ÔÚͬһ¾ùÔȽéÖÊÖÐÔÈËÙ´«²¥£¬Äܸù¾ÝÖʵãµÄλÖúÍÔ˶¯·½Ïòд³öÖʵãµÄÕñ¶¯·½³Ì£¬ÒªÖªµÀÖʵãÔÚÒ»¸öÖÜÆÚÄÚͨ¹ýµÄ·³ÌÊÇËı¶µÄÕñ·ù£®¸ù¾Ýʱ¼äÓëÖÜÆڵı¶Êý¹Øϵ£¬ÇóÖʵãͨ¹ýµÄ·³Ì£®
A£® | ±äѹÆ÷¿ÉÒԸı佻±äµçѹµ«²»ÄܸıäƵÂÊ | |
B£® | ¶óÁ÷Ȧ¶Ô½»Á÷µÄ×è°×÷ÓÃÖ÷ÒªÊÇÒòΪÏßȦ´æÔÚµç×è | |
C£® | µç´Å¯ÊÇÀûÓõç´Å¸ÐÓ¦ÎÐÁ÷µÄ¼ÓÈÈÔÀí | |
D£® | ÕòÁ÷Æ÷µÄ×Ô¸ÐϵÊýºÜ´ó£¬Æô¶¯ÈÕ¹âµÆʱ£¬ÕòÁ÷Æ÷ÀûÓÃ×Ô¸ÐÏÖÏó²úÉú˲ʱ¸ßѹ |
A£® | A1µÄʾÊý²»±ä£¬A2µÄʾÊý²»±ä | B£® | A1µÄʾÊý¼õС£¬A2µÄʾÊý¼õС | ||
C£® | V1µÄʾÊý¼õС£¬V2µÄʾÊý¼õС | D£® | V1µÄʾÊýÔö´ó£¬V2µÄʾÊýÔö´ó |
A£® | SÓë1¡¢2Á¬½Óʱ£¬¶àÓõç±í¾Í³ÉÁ˵çÁ÷±í£¬½Ó1Á¿³Ì±È½Ó2Á¿³Ì´ó | |
B£® | SÓë3¡¢4Á¬½Óʱ£¬¶àÓõç±í¾Í³ÉÁ˵çÁ÷±í | |
C£® | SÓë3¡¢4Á¬½Óʱ£¬¶àÓõç±í¾Í³ÉÁ˵çѹ±í | |
D£® | SÓë5Á¬½Óʱ£¬¶àÓõç±í¾Í³ÉÁËÅ·Ä·±í |