Question

Èçͼ2¡ª12Ëùʾµç·ÖУ¬µçÔ´µç¶¯ÊÆE = 40 V£¬ÄÚ×èr = 0.2¦¸£¬Ëü¶ÔÁ½¸ö¡°36V 36W¡±µÄµÆÅÝL₁ºÍL₂¹©µç¡£¶¨Öµµç×èR₂ºÍ»¬¶¯±ä×èÆ÷R₁ÓÃÀ´¿ØÖƵÆÅݵÄÁÁ¶È¡£R₁µÄ×î´ó×èÖµÊÇ60¦¸¡£µ±R₁µ÷½Úµ½×îСֵʱ£¬Á½¸öµÆÅÝÇ¡ºÃÕý³£·¢¹â£¬ÉèµÆÅݵĵç×è¹Ì¶¨²»±ä¡£Ç󣺣¨1£©µç×èR₂µÄ×èֵΪ¶à´ó£¿£¨2£©ÔÚµÆÅÝÕý³£·¢¹âʱ£¬R₂ÉÏÏûºÄµÄ¹¦ÂÊΪ¶àÉÙ£¿£¨3£©R₁µ÷½Úµ½×î´óʱ£¬µÆÅÝL₁ÉÏÏûºÄµÄʵ¼Ê¹¦ÂÊΪ¶àÉÙ£¿

Answer 1

£¨1£©µ±R₁µ÷½Úµ½×îСʱ£¬R₁ = 0£¬Á½µÆÅÝÕý³£·¢¹â£¬ËùÒÔͨ¹ýÁ½µÆÅݵĵçÁ÷ΪµÆÅݵĶµçÁ÷£¬Îª£º

I_µÆ1 = I_µÆ2 = I_µÆ¶î = P_µÆ¶î/U_µÆ¶î = 36/36 = 1£¨A£©£¬¡­¡­¡­¡­¡­¡­£¨2·Ö£©

¸É·ÖеÄ×ܵçÁ÷Ϊ£ºI = 2I_µÆ = 2¡Á1 = 2£¨A£©£¬¡­¡­¡­¡­¡­¡­¡­£¨1·Ö£©

R₂Á½¶ËµçѹΪ£ºU_R2 = E ¨D U_µÆ¨D Ir£¬¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­£¨1·Ö£©

ËùÒÔµç×èR₂µÄ×èֵΪ£ºR₂ = =  = 1.8£¨¦¸£©£¨1·Ö£©

    £¨2£©ÔÚµÆÅÝÕý³£·¢¹âʱ£¬µç×èR₂ÏûºÄµÄ¹¦ÂÊΪ£º

P_R2 = I²R₂ = 2²¡Á1.8 = 7.2£¨W£©¡£¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­£¨2·Ö£©

£¨3£©µ±R₁µ÷½Úµ½×î´óֵʱ£¬R₁ = 60¦¸£¬ÔòµÆÅݵĵç×èΪ£º

R_L1 = R_L2 = U²_µÆ¶î/P_µÆ¶î = 36²/36 = 36£¨¦¸£©£¬

µÆµÄ²¢Áªµç×èΪ£ºR_µÆ²¢ = R_L1/2 = 18£¨¦¸£©¡­¡­¡­¡­¡­¡­¡­¡­¡­£¨1·Ö£©

¸ù¾ÝÈ«µç·ŷķ¶¨ÂÉÓУº

I¡¯ = = = 0.5£¨A£©£¬¡­£¨2·Ö£©

µÆÅÝÁ½¶ËµÄµçѹΪ£ºU_µÆ=E-I£¨R₁+R₂+r£©=40-0.5¡Á62=9£¨V£©£¬£¨1·Ö£©

µÆÅÝL₁ʵ¼ÊÏûºÄµÄ¹¦ÂÊΪ£ºP_L1ʵ¼Ê=U²_µÆ/R_µÆ1=9²/36=2.25£¨W£©¡££¨1·Ö£©

½âÎö:

ÂÔ