ÌâÄ¿ÄÚÈÝ
3£®ÈçͼËùʾ£¬Æ½ÐнðÊôµ¼¹ìÓëˮƽÃæ³É¦È½Ç£¬µ¼¹ìÓë¹Ì¶¨µç×èR1ºÍR2ÏàÁ¬£¬ÔÈÇ¿´Å³¡´¹Ö±´©¹ýµ¼¹ìƽÃ森ÓÐÒ»µ¼Ìå°ôab£¬ÖÊÁ¿Îªm£¬µ¼Ìå°ôµÄµç×èÓë¹Ì¶¨µç×èR1ºÍR2µÄ×èÖµ¾ùÏàµÈ£¬Óëµ¼¹ìÖ®¼äµÄ¶¯Ä¦²ÁÒòÊýΪ¦Ì£¬µ¼Ìå°ôabÑص¼¹ìÏòÉÏ»¬¶¯£¬µ±ÉÏ»¬µÄËÙ¶ÈΪVʱ£¬Êܵ½°²ÅàÁ¦µÄ´óСΪF£®´Ëʱ£¨¡¡¡¡£©A£® | µç×èR1ÏûºÄµÄÈȹ¦ÂÊΪ$\frac{Fv}{3}$ | |
B£® | µç×è R1ÏûºÄµÄÈȹ¦ÂÊΪ$\frac{Fv}{6}$ | |
C£® | Õû¸ö×°ÖÃÒòĦ²Á¶øÏûºÄµÄÈȹ¦ÂÊΪ¦Ìmgvcos¦È | |
D£® | Õû¸ö×°ÖÃÏûºÄµÄ»úе¹¦ÂÊΪ£¨F+¦Ìmgcos¦È£©v |
·ÖÎö µç×èR1¡¢R2²¢ÁªÓëµ¼Ìå°ô´®Áª£®ÓɸÐÓ¦µç¶¯Êƹ«Ê½E=BLv¡¢Å·Ä·¶¨ÂÉ¡¢°²ÅàÁ¦¹«Ê½£¬ÍƵ¼°²ÅàÁ¦ÓëËٶȵĹØϵʽ£®Óɹ¦Âʹ«Ê½µç×èµÄ¹¦ÂÊ¡¢Èȹ¦Âʼ°»úе¹¦ÂÊ£®
½â´ð ½â£ºA¡¢Éèab³¤¶ÈΪL£¬´Å¸ÐӦǿ¶ÈΪB£¬µç×èR1=R2=R£®µç·ÖиÐÓ¦µç¶¯ÊÆE=BLv£¬abÖиÐÓ¦µçÁ÷Ϊ£º
I=$\frac{E}{R+\frac{R}{2}}$=$\frac{2BLv}{3R}$£¬
abËùÊÜ°²ÅàÁ¦Îª£ºF=BIL=$\frac{2{B}^{2}{L}^{2}v}{3R}$¡¢Ù£¬
µç×èR1ÏûºÄµÄÈȹ¦ÂÊΪ£ºP1=£¨$\frac{1}{2}$I£©2R=$\frac{{B}^{2}{L}^{2}{v}^{2}}{9R}$¡¢Ú£¬
Óɢ٢ڵã¬P1=$\frac{1}{6}$Fv£¬µç×èR1ºÍR2×èÖµÏàµÈ£¬ËüÃÇÏûºÄµÄµç¹¦ÂÊÏàµÈ£¬ÔòP1=P2=$\frac{1}{6}$Fv£¬¹ÊA´íÎó£¬BÕýÈ·£®
C¡¢Ä¦²ÁÁ¦´óСf=¦Ìmgcos¦Á£¬¹ÊÕû¸ö×°ÖÃÒòĦ²Á¶øÏûºÄµÄÈȹ¦ÂÊΪ£ºPf=fv=¦Ìmgcos¦Á•v=¦Ìmgvcos¦Á£¬¹ÊCÕýÈ·£»
D¡¢Õû¸ö×°ÖÃÏûºÄµÄ»úе¹¦ÂÊΪ£ºP3=Fv+P2=£¨F+¦Ìmgcos¦Á£©v£¬¹ÊDÕýÈ·£®
¹ÊÑ¡£ºBCD£®
µãÆÀ ½â¾ö±¾ÌâÊǸù¾Ý·¨ÀµÚµç´Å¸ÐÓ¦¶¨ÂÉ¡¢Å·Ä·¶¨ÂÉÍƵ¼³ö°²ÅàÁ¦ÓëËٶȵıí´ïʽ£¬½áºÏ¹¦Âʹ«Ê½ºÍ¹¦ÄܹØϵ½øÐзÖÎö£®
A£® | À뿪´Å³¡ÇøÓò¹ý³ÌÖеĵçÁ÷·½ÏòΪdcbad | |
B£® | ͨ¹ý´Å³¡ÇøÓò¹ý³ÌÖеÄ×îСËÙ¶ÈΪ$\sqrt{\frac{2FL}{m}}$ | |
C£® | ͨ¹ý´Å³¡ÇøÓò¹ý³ÌÖеĽ¹¶úÈÈΪ2FL | |
D£® | ½øÈë´Å³¡ÇøÓò¹ý³ÌÖÐÊܵ½µÄ°²ÅàÁ¦µÄ³åÁ¿´óСΪ$\frac{{{B^2}{L^3}}}{R}$ |
A£® | 3£º2 | B£® | 1£º3 | C£® | $\sqrt{3}$£º1 | D£® | 2£º$\sqrt{3}$ |
A£® | ·Ö×ÓÊÆÄÜËæ×Å·Ö×Ó¼ä¾àÀëµÄÔö´ó£¬¿ÉÄÜÏȼõСºóÔö´ó | |
B£® | ÎïÌåÎüÊÕÈÈÁ¿£¬Î¶ÈÒ»¶¨Éý¸ß | |
C£® | ½þÈóÓë²»½þÈóÊÇ·Ö×ÓÁ¦×÷ÓõıíÏÖ | |
D£® | ÌìȻʯӢ±íÏÖΪ¸÷ÏòÒìÐÔ£¬ÊÇÓÉÓÚ¸ÃÎïÖʵÄ΢Á£ÔÚ¿Õ¼äµÄÅÅÁв»¹æÔò | |
E£® | ÈÈÁ¿¿ÉÒÔ×Ô·¢µØ´Ó·Ö×Óƽ¾ù¶¯ÄÜ´óµÄÎïÌå´«¸ø·Ö×Óƽ¾ù¶¯ÄÜСµÄÎïÌå |