ÌâÄ¿ÄÚÈÝ
1£®Èçͼ¼×Ëùʾ£¬Ò»Æ½ÐаåµçÈÝÆ÷¼«°å³¤l=10cm£¬¿ía=8cm£¬Á½¼«°å¼ä¾àΪd=4cm£¬¾à¼«°åÓÒ¶Ë$\frac{1}{2}$´¦ÓÐÒ»ÊúÖ±·ÅÖõÄÓ«¹âÆÁ£®ÔÚƽÐаåµçÈÝÆ÷×ó²àÓÐÒ»³¤b=8cmµÄ¡°ÏÁ·ì¡±Á£×ÓÔ´£¬¿ÉÑØ×ÅÁ½°åÖÐÐÄƽÃ棬¾ùÔÈ¡¢Á¬Ðø²»¶ÏµØÏòµçÈÝÆ÷ÄÚÉäÈë±ÈºÉΪ2¡Á1010C/kg£¬ËÙ¶ÈΪ4¡Á106m/sµÄ´øµçÁ£×Ó£®ÏÖÔÚƽÐаåµçÈÝÆ÷µÄÁ½¼«°å¼ä¼ÓÉÏÈçͼÒÒËùʾµÄ½»Á÷µç£¬ÒÑÖªÁ£×ÓÔÚµçÈÝÆ÷ÖÐÔ˶¯ËùÓõÄʱ¼äԶСÓÚ½»Á÷µçµÄÖÜÆÚ£®ÏÂÃæ˵·¨ÕýÈ·µÄÊÇ£¨¡¡¡¡£©A£® | Á£×Ó´òµ½ÆÁÉÏʱÔÚÊúÖ±·½ÏòÉÏÆ«ÒƵÄ×î´ó¾àÀëΪ6.25cm | |
B£® | Á£×Ó´òÔÚÆÁÉϵÄÇøÓòÃæ»ýΪ64cm2 | |
C£® | ÔÚ0-0.02sÄÚ£¬½øÈëµçÈÝÆ÷ÄÚµÄÁ£×ÓÓÉ64%Á£×ÓÄܹ»´òÔÚÆÁÉÏ | |
D£® | ÔÚ0-0.002sÄÚ£¬ÆÁÉϳöÏÖÁÁÏßµÄʱ¼äΪ0.0128s |
·ÖÎö Àë×Ó½øÈëµç³¡ºó×öÀàƽÅ×Ô˶¯£¬ÏÈÓÉÀàƽÅ×Ô˶¯µÄ֪ʶÇó³öÀë×ÓÇ¡ºÃ´Ó¼«°å±ßÔµÉä³öʱµÄµçѹ£¬ÀûÓÃÍÆÂÛ£¬Çó³öÀë×Ó´òÔÚÆÁÉÏ×î´óµÄƫת¾àÀ룮¼´¿ÉµÃµ½Àë×Ó´òÔÚÆÁÉϵÄÇøÓòÃæ»ý£»¸ù¾ÝÁÙ½çÇé¿öµÄµçѹ£¬Çó³öÔÚÒ»¸öÖÜÆÚÄÚ£¬Àë×Ó´òµ½ÆÁÉϵÄʱ¼ä£®
½â´ð ½â£ºAB¡¢ÉèÀë×ÓÇ¡ºÃ´Ó¼«°å±ßÔµÉä³öʱµÄµçѹΪU0
ˮƽ·½Ïò£ºl=v0t¡¢Ù
ÊúÖ±·½Ïò£º$\frac{d}{2}$=$\frac{1}{2}$at2¡¢Ú
ÓÖa=$\frac{q{U}_{0}}{md}$¡¢Û
Óɢ٢ڢ۵ãºU0=$\frac{m{d}^{2}{U}_{0}^{2}}{q{l}^{2}}$=128V
µ±U¡Ý128VʱÀë×Ó´òµ½¼«°åÉÏ£¬µ±U£¼128Vʱ´òµ½ÆÁÉÏ£¬¿ÉÖª£¬Àë×Óͨ¹ýµç³¡Æ«×ª¾àÀë×î´óΪ$\frac{1}{2}$d£®
ÀûÓÃÍÆÂÛ£º´òµ½ÆÁµÄÀë×ÓºÃÏñÊÇ´Ó¼«°åÖÐÐÄÑØÖ±ÏßÉäµ½ÆÁÉÏ£®
ÓÉÈý½ÇÐÎÏàËƿɵãº$\frac{\frac{l}{2}+\frac{l}{2}}{\frac{l}{2}}$=$\frac{y}{\frac{d}{2}}$
½âµÃ´òµ½ÆÁÉϵij¤¶ÈΪ£ºy=d=4cm£¬
ÓÖÓɶԳÆÖª£¬Àë×Ó´òÔÚÆÁÉϵÄ×ܳ¤¶ÈΪ2d£¬ÇøÓòÃæ»ýΪS=2y•a=2ad=64cm2£¬¹ÊA´íÎó£¬BÕýÈ·£»
C¡¢Á£×Ó´òÔÚÆÁÉϵıÈÀýΪ$\frac{128}{200}$%=64%£¬ÔÚ0-0.02sÄÚ£¬½øÈëµçÈÝÆ÷ÄÚµÄÁ£×ÓÓÉ64%Á£×ÓÄܹ»´òÔÚÆÁÉÏ£¬¹ÊCÕýÈ·£»
D¡¢ÔÚÇ°$\frac{1}{4}$T£¬Àë×Ó´òµ½ÆÁÉϵÄʱ¼ät0=$\frac{128}{200}$¡Á0.005s=0.0032 s£»ÓÖÓɶԳÆÐÔÖª£¬ÔÚÒ»¸öÖÜÆÚÄÚ£¬´òµ½ÆÁÉϵÄ×Üʱ¼ät=4t0=0.0128s£®¹ÊDÕýÈ·£®
¹ÊÑ¡£ºBCD£®
µãÆÀ ±¾ÌâÊÇÀàƽÅ×Ô˶¯µÄÎÊÌ⣬²ÉÓÃÔ˶¯µÄ·Ö½â·½·¨´¦Àí£¬¹Ø¼üÊÇÍÚ¾òÒþº¬µÄÁÙ½çÌõ¼þ£¬²¢ÇÒÇÉÃîÀûÓÃÍÆÂÛ½øÐÐÑо¿£®
A£® | 2£º1 | B£® | 8£º1 | C£® | 16£º1 | D£® | 25£º8l |
A£® | ´ÅÁ÷Ìå·¢¶¯»ú | B£® | µç×ÓÏÔÏñ¹Ü | C£® | »ØÐý¼ÓËÙÆ÷ | D£® | ÑÓʱ¼ÌµçÆ÷ |
A£® | µçÁ÷±í²âµÃµÄÊǵçÁ÷×î´óÖµ | |
B£® | ¸ÐÓ¦µç¶¯ÊƵÄ˲ʱֵ±í´ïʽΪe=NBS¦Ø•sin¦Øt | |
C£® | PÏòÉÏÒƶ¯Ê±£¬µçÁ÷±íʾÊý±ä´ó | |
D£® | PÏòÉÏÒƶ¯Ê±£¬±äѹÆ÷ÔÏßȦµÄ¹¦Âʱä´ó |
A£® | ÕâÁв¨µÄ´«²¥ËÙ¶ÈΪ0.2m/s | |
B£® | ÔÚt=0ʱ¿Ì£¬ÖʵãPÏòÉÏÔ˶¯ | |
C£® | ÔÚt2=0.4sʱ¿Ì£¬ÖʵãA¾ßÓÐ×î´óµÄÕýÏò¼ÓËÙ¶È | |
D£® | ÔÚt3=0.7sʱ¿Ì£¬ÖʵãQÊ×´ÎλÓÚ²¨·å |
A£® | ²¨³¤Îª4m | B£® | ²¨ËÙΪ2m/s | ||
C£® | 3sÄ©A¡¢BÁ½ÖʵãµÄλÒÆÏàͬ | D£® | 1sÄ©AµãµÄËٶȴóÓÚBµãµÄËÙ¶È |