Question

1£®ÈçͼËùʾ£¬Ôڹ⻬ˮƽÃæÉϵÄÖ±ÏßMN×ó²àÓд¹Ö±ÓÚÖ½ÃæÏòÀïµÄÔÈÇ¿´Å³¡£¬ÓÒ²àÊÇÎ޴ų¡¿Õ¼ä£®½«Á½¸ö´óСÏàͬµÄÍ­ÖʾØÐαպÏÏß¿òÓÉͼʾλÖÃÒÔͬÑùµÄËÙ¶ÈvÏòÓÒÍêÈ«À­³öÔÈÇ¿´Å³¡£®ÒÑÖªÖÆ×÷ÕâÁ½Ö»Ïß¿òµÄÍ­Öʵ¼Ïߵĺá½ØÃæ»ýÖ®±ÈÊÇ1£º2£®ÔòÀ­³ö¹ý³ÌÖÐÏÂÁÐ˵·¨ÖÐÕýÈ·µÄÊÇ£¨¡¡¡¡£©

• A£® ËùÓÃÀ­Á¦´óС֮±ÈΪ2£º1
• B£® ͨ¹ýµ¼Ïßijһºá½ØÃæµÄµçºÉÁ¿Ö®±ÈÊÇ1£º2
• C£® À­Á¦×ö¹¦Ö®±ÈÊÇ2£º1
• D£® Ïß¿òÖвúÉúµÄµçÈÈÖ®±ÈΪ1£º2

Answer 1

·ÖÎö ¸ù¾ÝE=BLv¡¢I=$\frac{E}{R}$¡¢F=BIL£¬R=¦Ñ$\frac{L}{S}$µÃµ½°²ÅàÁ¦µÄ±í´ïʽ£¬¼´¿É¸ù¾ÝƽºâÌõ¼þµÃµ½À­Á¦µÄ´óС¹Øϵ£»¸ù¾Ý¸ÐÓ¦µçºÉÁ¿q=$\frac{¡÷¦µ}{R}$·ÖÎöµçºÉÁ¿µÄ¹Øϵ£»Óɹ¦µÄ¹«Ê½µÃµ½À­Á¦×ö¹¦µÄ±í´ïʽ£¬ÔÙÇó½â×ö¹¦Ö®±È£»¸ù¾Ý¹¦ÄܹØϵ·ÖÎöµçÈÈÖ®±È£®

½â´ð ½â£ºA¡¢Éè¾ØÐÎÏßȦ×óÓұ߳¤ÎªL₁£¬ÉÏϱ߳¤ÎªL₂£®µç×èÂÊΪ¦Ñ£¬½ØÃæ»ýΪS£®
Ôò¸ÐÓ¦µçÁ÷Ϊ I=$\frac{E}{R}$=$\frac{B{L}_{1}v}{¦Ñ\frac{2£¨{L}_{1}+{L}_{2}£©}{S}}$
À­Á¦ F=BIL₁=$\frac{{B}^{2}{L}_{1}^{2}v}{¦Ñ\frac{2£¨{L}_{1}+{L}_{2}£©}{S}}$=$\frac{{B}^{2}{L}_{1}^{2}vS}{2¦Ñ£¨{L}_{1}+{L}_{2}£©}$£¬ÔòÖªF¡ØS£¬ËùÒÔËùÓÃÀ­Á¦´óС֮±ÈΪ1£º2£®¹ÊA´íÎó£®
B¡¢¸ù¾Ý¸ÐÓ¦µçºÉÁ¿ q=$\frac{¡÷¦µ}{R}$=$\frac{B{L}_{1}{L}_{2}}{¦Ñ\frac{2£¨{L}_{1}+{L}_{2}£©}{S}}$=$\frac{B{L}_{1}{L}_{2}S}{2¦Ñ£¨{L}_{1}+{L}_{2}£©}$¡ØS£¬ËùÒÔͨ¹ýµ¼Ïßijһºá½ØÃæµÄµçºÉÁ¿Ö®±ÈÊÇ1£º2£®¹ÊBÕýÈ·£®
C¡¢À­Á¦×ö¹¦ W=FL₁=$\frac{{B}^{2}{L}_{1}^{2}vS}{2¦Ñ£¨{L}_{1}+{L}_{2}£©}$•L₁¡ØS£¬À­Á¦×ö¹¦Ö®±ÈÊÇ1£º2£®¹ÊC´íÎó£®
D¡¢¸ù¾Ý¹¦ÄܹØϵ¿ÉÖª£¬Ïß¿òÖвúÉúµÄµçÈȵÈÓÚÀ­Á¦×ö¹¦£¬¹ÊµçÈÈÖ®±ÈΪ1£º2£®¹ÊDÕýÈ·£®
¹ÊÑ¡£ºBD

µãÆÀ ±¾ÌâÊǵç´Å¸ÐÓ¦Óëµç·¡¢Á¦Ñ§ÖªÊ¶µÄ×ۺϣ¬ÒªÕÆÎÕµ¼ÌåÇиî²úÉúµÄ¸ÐÓ¦µç¶¯Êƹ«Ê½£¬±ÕºÏµç·ŷķ¶¨ÂÉ¡¢µç×趨ÂÉ¡¢¸ÐÓ¦µçºÉÁ¿µÈ¶à¸ö֪ʶ£¬ÍƵ¼³öËùÇóÁ¿µÄ±í´ïʽÊǹؼü£®