µç·»ù´¡¿ÎºóϰÌâ´ð°¸£¨×¨¿Æ½Ì²Ä£©[1] ÏÂÔØ±¾ÎÄ

µÚ1Õ ÕºóϰÌâ½âÎö

1.1 Ò»Ö»¡°100¦¸¡¢100 W¡±µÄµç×èÓë120 VµçÔ´Ïà´®Áª£¬ÖÁÉÙÒª´®Èë¶à´óµÄµç×è R²ÅÄÜʹ¸Ãµç×èÕý³£¹¤×÷£¿µç×èRÉÏÏûºÄµÄ¹¦ÂÊÓÖΪ¶àÉÙ£¿

½â£ºµç×èÔÊÐíͨ¹ýµÄ×î´óµçÁ÷Ϊ

P100??1A R'100120120ËùÒÔÓ¦ÓÐ 100?R?£¬Óɴ˿ɽâµÃ£ºR??100?20?

11µç×èRÉÏÏûºÄµÄ¹¦ÂÊΪ P=12¡Á20=20W

I?1.2 ͼ1.27£¨a£©¡¢£¨b£©µç·ÖУ¬ÈôÈÃI=0.6A£¬R=£¿ ͼ1.27£¨c£©¡¢£¨d£©µç·ÖУ¬ÈôÈÃU=0.6V£¬R=£¿

2A I 3¦¸ R (a) £« 3V £­ I 3¦¸ R (b) 2A £« U R £­ (c) 3¦¸

£« 3¦¸ 3V £« £­ U R £­ (d) ͼ1.27 ϰÌâ1.2µç·ͼ

½â£º(a)ͼµç·ÖУ¬3¦¸µç×èÖÐͨ¹ýµÄµçÁ÷Ϊ I¨@=2£­0.6=1.4A RÓë3¦¸µç×èÏಢÁª£¬¶ËµçѹÏàͬÇÒΪ U=1.4¡Á3=4.2V ËùÒÔ R=4.2¡Â0.6=7¦¸

(b)ͼµç·ÖУ¬3¦¸µç×èÖÐͨ¹ýµÄµçÁ÷Ϊ I¨@=3¡Â3=1A RÓë3¦¸µç×èÏಢÁª£¬¶ËµçѹÏàͬ£¬Òò´Ë R=3¡Â0.6=5¦¸ (c)ͼµç·ÖУ¬RÓë3¦¸µç×èÏà´®Áª£¬Í¨¹ýµÄµçÁ÷Ïàͬ£¬Òò´Ë

R=0.6¡Â2=0.3¦¸

(d)ͼµç·ÖУ¬3¦¸µç×èÁ½¶ËµÄµçѹΪ U¨@=3£­0.6=2.4V RÓë3¦¸µç×èÏà´®Áª£¬Í¨¹ýµÄµçÁ÷ÏàͬÇÒΪ I=2.4¡Â3=0.8A ËùÒÔ R=0.6¡Â0.8=0.75¦¸

1.3 Á½¸ö¶î¶¨Öµ·Ö±ðÊÇ¡°110V£¬40W¡±¡°110V£¬100W¡±µÄµÆÅÝ£¬ÄÜ·ñ´®Áªºó½Óµ½220VµÄµçÔ´ÉÏʹÓã¿Èç¹ûÁ½Ö»µÆÅݵĶ¹¦ÂÊÏàͬʱÓÖÈçºÎ£¿

½â£ºÁ½¸ö¶î¶¨µçѹֵÏàͬ¡¢¶î¶¨¹¦Âʲ»µÈµÄµÆÅÝ£¬ÆäµÆË¿µç×èÊDz»Í¬µÄ£¬¡°110V£¬40W¡±µÆÅݵĵÆË¿µç×èΪ£º R40U21102???302.5?;¡°110V£¬100W¡±µÆÅݵĵÆË¿µç×èΪ£ºP40U21102R100???121?£¬Èô´®Áªºó½ÓÔÚ220VµÄµçÔ´ÉÏʱ£¬Æäͨ¹ýÁ½µÆÅݵĵçÁ÷Ïàͬ£¬ÇÒ

P100220Ϊ£ºI??0.52A£¬Òò´Ë40WµÆÅÝÁ½¶Ëʵ¼ÊËù¼ÓµçѹΪ£º

302.5?121U40?0.52?302.5?157.3V£¬ÏÔÈ»Õâ¸öµçѹ³¬¹ýÁ˵ÆÅݵĶֵ£¬¶ø100 WµÆÅÝÁ½¶Ëʵ¼Ê

Ëù¼ÓµçѹΪ£ºU100=0.52¡Á121=62.92V£¬Æäʵ¼ÊµçѹµÍÓڶֵ¶ø²»ÄÜÕý³£¹¤×÷£¬Òò´Ë£¬ÕâÁ½¸ö¹¦Âʲ»ÏàµÈµÄµÆÅÝÊDz»ÄÜ´®Áªºó½Óµ½220V

£« US £­ R IS A £« US £­ B (a) (b)

ͼ1.28 ϰÌâ1.4µç·ͼ

A R IS µçÔ´ÉÏʹÓõġ£ÈôÁ½Ö»µÆÅݵĶ¹¦ÂÊÏàͬʱ£¬ÓÉÓÚµÆË¿µç×èÒ²Ïàͬ£¬Òò´Ë·ÖѹÏàµÈ£¬ÊÇ¿ÉÒÔ´®Áªºó½ÓÔÚ220VµçÔ´ÉÏʹÓõġ£

1.4 ͼ1.28Ëùʾµç·ÖУ¬ÒÑÖªUS=6V£¬IS=3A£¬R=4¦¸¡£¼ÆËãͨ¹ýÀíÏëµçѹԴµÄµçÁ÷¼°ÀíÏëµçÁ÷Ô´Á½¶ËµÄµçѹ£¬²¢¸ù¾ÝÁ½¸öµçÔ´¹¦ÂʵļÆËã½á¹û£¬ËµÃ÷ËüÃÇÊDzúÉú¹¦ÂÊ»¹ÊÇÎüÊÕ¹¦ÂÊ¡£

½â£º£¨a£©Í¼µç·ÖУ¬ÈýÔª¼þΪ´®Áª¹ØÏµ£¬Òò´Ëͨ¹ýµÄµçÁ÷Ïàͬ£¬Òò´Ë¸ù¾ÝKVL¶¨ÂÉ¿ÉÁгöµçѹ·½³ÌΪ£ºUAB£­US£«ISR£¬Òò´Ë¿ÉµÃºãÁ÷Ô´¶ËµçѹUAB=6£­3¡Á4=£­6V¡£¸ù¾ÝÕâÒ»½á¹û¿É¼ÆËã³öÀíÏëµçÁ÷Ô´ÉÏÎüÊյŦÂÊΪ£ºP= IS¡Á(£­UAB)=3¡Á(£­6)=£­18W£¬ÎüÊÕ¸º¹¦ÂÊ˵Ã÷ÀíÏëµçÁ÷Դʵ¼ÊÉÏÊÇ·¢³ö¹¦ÂÊ£»ÀíÏëµçѹԴµÄµçѹÓëͨ¹ýËüµÄµçÁ÷Ϊ·Ç¹ØÁª·½Ïò£¬·¢³öµÄ¹¦ÂÊΪ£ºP= IS¡ÁUS=3¡Á6=18W£¬Õýֵ˵Ã÷ÀíÏëµçѹԴµÄÈ·ÊÇÏòÍ⹩³öµçÄÜ£»¸ºÔØRÉÏÏûºÄµÄ¹¦ÂÊΪP= IS2R=32¡Á4=36W£¬Á½¸öÀíÏëµçÔ´·¢³öµÄ¹¦ÂÊÇ¡ºÃµÈÓÚµç×èÉÏÏûºÄµÄ¹¦ÂÊ£¬·ÖÎö½á¹ûÕýÈ·¡£

£¨b£©Í¼µç·ÖУ¬ÈýÔª¼þΪ²¢Áª¹ØÏµ£¬Òò´Ë¶ËµçѹÏàµÈ£¬¸ù¾ÝÅ·Ä·¶¨ÂɿɵÃRÖÐͨ¹ýµÄµçÁ÷Ϊ£ºI¨@=US¡ÂR=6¡Â4=1.5A£¨ÓÉAµãÁ÷³ö£©£¬¶ÔAµãÁÐÒ»KCL·½³ÌÓֿɵóöÀíÏëµçѹԴÖÐͨ¹ýµÄµçÁ÷I¡å=3£­1.5=1.5A£¨ÓÉAµãÁ÷³ö£©¡£¸ù¾ÝÕâÒ»½á¹û¿É¼ÆËã³öÀíÏëµçÁ÷Ô´ÉÏ·¢³öµÄ¹¦ÂÊΪ£ºP= IS¡ÁUS=3¡Á6=18W£»ÀíÏëµçѹԴµÄµçѹÓëͨ¹ýËüµÄµçÁ÷Ϊ¹ØÁª·½Ïò£¬ÎüÊյŦÂÊΪ£ºP= I¡å¡ÁUS=1.5¡Á6=9W£»¸ºÔØRÉÏÏûºÄµÄ¹¦ÂÊΪP= I¨@2R=1.52¡Á4=9W£¬ÀíÏëµçÁ÷Ô´·¢³öµÄ¹¦ÂÊÇ¡ºÃµÈÓÚÀíÏëµçѹԴºÍµç×èÉÏÏûºÄµÄ¹¦ÂÊ£¬·ÖÎö½á¹ûÕýÈ·¡£

1.5 µç·Èçͼ1.29Ëùʾ£¬ÒÑÖªUS=100V£¬R1=2K¦¸£¬R2=8K¦¸£¬ÔÚÏÂÁÐ3ÖÖÇé¿öÏ£¬·Ö±ðÇóµç×èR2Á½¶ËµÄµçѹ¼°R2¡¢R3ÖÐͨ¹ýµÄµçÁ÷¡£¢ÙR3=8K¦¸£»¢ÚR3=¡Þ£¨¿ªÂ·£©£»¢ÛR3=0£¨¶Ì·£©¡£

½â£º¢ÙR23= R2¡ÎR3=8¡Î8=4K¦¸£¬¸ù¾Ý·Öѹ¹«Ê½¿ÉÇóµÃµç×èR2Á½¶ËµÄµçѹΪ

UR2?USR23100?4??66.7V

R1?R232?4R1 £« US £­ R2 R3

I3?I2?UR2?R2?66.7?8?8.33mA

¢ÚR3=¡Þʱ£¬Í¨¹ýËüµÄµçÁ÷ΪÁ㣬´ËʱR2µÄ¶ËµçѹΪ

R2100?8??80V UR2?USR1?R22?8ͼ1.29 ϰÌâ1.5µç· I £« 1V £­ A 3¦¸ £« U £­

I2?UR2?R2?80?8?10mA

¢ÛR3=0ʱ£¬R2±»¶Ì·£¬Æä¶ËµçѹΪÁ㣬ËùÒÔ

I2=0£¬I3?2¦¸ 1A US100??50mA¡£ R12ͼ1.30 ϰÌâ1.6µç·

1.6 µç·Èçͼ1.30Ëùʾ£¬ÇóµçÁ÷IºÍµçѹU¡£

½â£º¶ÔÓÒ»ØÂ·ÁÐÒ»¸öKVL·½³Ì£¨Ñ¡Ë³Ê±ÕëÈÆÐз½Ïò£©£º U£­1+1¡Á3=0 ¿ÉµÃU=1£­1¡Á3=£­2V ¶ÔAµãÁÐÒ»¸öKCL·½³ÌI£­1¡Â2£­1=0¿ÉµÃ I=1¡Â2£«1=1.5A

1.7Çóͼ1.31Ëùʾ¸÷µç·µÄÈë¶Ëµç×èRAB¡£

½â£º£¨a£©Í¼£ºRAB=2£«[£¨3¡Î9£«6£©¡Î8]¡Ö6.06¦¸ £¨b£©Í¼£ºRAB=1.2£«4£«[£¨3£«9£©¡Î£¨2£«6£©]¡Ö10¦¸

£¨c£©Í¼£ºRAB=0¦¸

£¨d£©Í¼£ºÊ×ÏȶÔ3¸öÈý½ÇÐÎÁ¬½ÓµÄµç×è½øÐÐY±ä»»£¬È»ºó¿ÉµÃ

RAB=10£«[£¨10£«30£©¡Î£¨10£«30£©]=30¦¸

30¦¸ a 2¦¸ 9¦¸ 3¦¸ 6¦¸ b £¨a£©

8¦¸

b £¨b£©

4¦¸ a 1.2¦¸ 3¦¸ 8¦¸ 9¦¸ 2¦¸

a 6¦¸

b £¨c£©

2¦¸ 4¦¸ 3¦¸ 3¦¸ 6¦¸

b a 30¦¸ 30¦¸ 30¦¸ 30¦¸ (d)

ͼ1.31 ϰÌâ1.7µç·

1.8 Çóͼ1.32Ëùʾµç·ÖеĵçÁ÷IºÍµçѹU¡£

I¡å 16¦¸ £« 12V £­ 7.5¦¸ £­U £« 8¦¸ 9¦¸ I¨@ ͼ1.32 ϰÌâ1.8µç·

9¦¸ 6¦¸ I

£« 12V £­ 24¦¸ I¨@ ϰÌâ1.8µÈЧµç·ͼ

12¦¸ I¡å

½â£ºÊ×ÏȰÑÔ­µç·µÈЧΪÓÒÉÏͼËùʾ£¬Çó³öI¡äºÍI¡å£º I¡ä=12¡Â24=0.5A I¡å=12¡Â12=1A Ôٻص½Ô­µç·¿ÉÇó³öµçÁ÷

I=1¡Á

9?9=0.75A

9?9?69¦¸µç×èÖÐͨ¹ýµÄµçÁ÷Ϊ1£­0.75=0.25A£¨·½ÏòÏòÏ£©£¬Òò´Ë

U=0.25¡Á9£­0.5¡Á8=6.25V

1.9 ¼ÙÉèͼ1.18£¨a£©µç·ÖУ¬US1=12V£¬US2=24V£¬RU1= RU2=20¦¸£¬R=50¦¸£¬ÀûÓõçÔ´µÄµÈЧ±ä»»·½·¨£¬Çó½âÁ÷¹ýµç×èRµÄµçÁ÷I¡£

½â£ºÓÉ£¨a£©Í¼µ½£¨b£©Í¼¿ÉµÃ IS1?1224?0.6A£¬IS2??1.2A£¬RI1?RI2?RU1?20? 2020 ÓÉ£¨b£©Í¼µ½£¨c£©Í¼¿ÉµÃ

IS?IS1?IS2?0.6?1.2?1.8A£¬RI?RI2//RI1?20//20?10? ¶Ôͼ£¨c£©Ó¦Ó÷ÖÁ÷¹«Ê½¿ÉµÃ

I?1.810?0.3A

10?50A I R R

£¨b£©

ͼ1.18 µç·ͼÓëµÈЧµç·ͼ IS1 RI1 IS2 I

RI2 B R

IS RI B £¨c£© A I R

RU2 £« US2 £­ A RU1 £« US1 £­ B £¨a£©

1.10 ³£ÓõķÖѹµç·Èçͼ1.33Ëùʾ£¬ÊÔÇ󣺢ٵ±¿ª¹ØS´ò¿ª£¬¸ºÔØRLδ½ÓÈëµç·ʱ£¬·ÖѹÆ÷µÄÊä³öµçѹU0£»¢Ú¿ª¹ØS±ÕºÏ£¬½ÓÈëRL=150¦¸Ê±£¬·ÖѹÆ÷µÄÊä³öµçѹU0£»¢Û¿ª¹ØS±ÕºÏ£¬½ÓÈëRL=15K¦¸£¬´Ëʱ·ÖѹÆ÷Êä³öµÄµçѹU0ÓÖΪ¶àÉÙ£¿²¢ÓɼÆËã½á¹ûµÃ³öÒ»¸ö½áÂÛ¡£

½â£º¢ÙS´ò¿ª£¬¸ºÔØRLδ½ÓÈëµç·ʱ

U0?200/2?100V£»

¢ÚS±ÕºÏ£¬½ÓÈëRL=150¦¸Ê±

£« 200V £­ 150¦¸ S U0?200150//150?66.7V£»

150//150?150150//15000?99.5V

150//15000?150150¦¸ RL ¢Û¿ª¹ØS±ÕºÏ£¬½ÓÈëRL=15K¦¸Ê±

ͼ1.33 ϰÌâ1.10µç·

U0?200ÏÔÈ»£¬¸ºÔصç×èÁ½¶ËµçѹµÄ¶àÉÙÈ¡¾öÓÚ¸ºÔصç×èµÄ×èÖµ£¬ÆäÖµÔ½´ó£¬·ÖµÃµÄµçѹԽ¶à¡£ 1.11 ÓõçѹԴºÍµçÁ÷Ô´µÄ¡°µÈЧ¡±·½·¨Çó³öͼ1.34Ëùʾµç·ÖеĿªÂ·µçѹUAB¡£

£«UAB £­ 2¦¸ £« 10V £­ 8¦¸ £­ 4V £« 9¦¸ 2¦¸ 1.6¦¸ 3A

£« 8V £­ 4V £« £­ ϰÌâ1.11µÈЧµç·

£«

6V £­

£«UAB £­ ͼ1.34 ϰÌâ1.11µç·

½â£ºÀûÓõçѹԴºÍµçÁ÷Ô´µÄ¡°µÈЧ¡±»¥»»£¬½«Ô­µç·µÈЧΪÓÒÏÂͼËùʾµç·£º ÓɵÈЧµç·¿ÉµÃ£ºUAB=8£­4£­6=£­2V

1.12µç·Èçͼ1.35Ëùʾ£¬ÒÑÖªÆäÖеçÁ÷I1=£­1A£¬US1=20V£¬US2=40V£¬µç×èR1=4¦¸£¬R2=10¦¸£¬Çóµç×èR3µÈÓÚ¶àÉÙÅ·¡£

½â£º²¢ÁªÖ§Â·µÄ¶Ëµçѹ

UAB= US1£­I1 R1=20£­(£­1)¡Á4=24V US2֧·µÄµçÁ÷¼ÙÉè·½ÏòÏòÉÏ£¬Ôò

R1 £« US1 £­ B

ͼ1.35 ϰÌâ1.12µç·

I1 A R2 £« US2 £­

U?UAB40?24??1.6A I2?S2R210¶Ô½áµãAÁÐKCL·½³Ì¿ÉÇó³öR3֧·µçÁ÷£¨¼ÙÉè²Î¿¼

R3