Question

3£®ÈçͼËùʾµÄµçѹÁ¦¹ø£¬¼¯Ñ¹Á¦¹ø¡¢µç·¹¹øµÄÓеãÒ»Ì壬ʡʱ½Úµç£¬ÈÈЧÂʸߣ®¸ÃµÄѹÁ¦¹ø¶î¶¨µçѹΪ220V£¬¼ÓÈÈʱµÄ¹¦ÂÊΪ900W£¬±£ÎÂʱµÄ×ܹ¦ÂÊÊǼÓÈÈʱ¹¦ÂʵÄ$\frac{1}{3}$£®µçѹÁ¦¹øÔÚÕý³£¹¤×÷ʱ£¬Çë½â´ðÏÂÁÐÎÊÌ⣨¼ÆËã½á¹û±£Áôµ½Ð¡Êýµãºóһ룩£®
£¨1£©µçѹÁ¦¹øÄÚÆøѹ´ó£¬ÒºÌåµÄ·Ðµã¸ß£¬ÖóÊìʳƷÓÃʱ¶Ì£¬ËùÒÔ½ÚÔ¼µçÄÜ£®
£¨2£©ÓõçѹÁ¦¹ø¼ÓÈÈʱ£¬Í¨¹ýµçÈÈË¿µÄµçÁ÷ºÍµçÈÈË¿µÄµç×è¸÷ÊǶàÉÙ£¿
£¨3£©ÈôµçѹÁ¦¹ø¼ÓÈÈ20min£¬±£ÎÂ10min£¬Ôڴ˹ý³ÌÖй²ÏûºÄµÄµçÄÜÊǶàÉÙkW•h£¿

Answer 1

·ÖÎö £¨1£©´ËÌâÊÇ¿¼²éÁËÆøѹÓë·ÐµãµÄ¹Øϵ£¬ÆøѹԽ¸ß£¬·ÐµãÔ½¸ß£¬ÕâÑùʳÎï»áÖóµÄÔ½¿ì£»
£¨2£©¸ù¾Ýµç¹¦ÂʵÄÓйع«Ê½P=UI¡¢P=$\frac{{U}^{2}}{R}$½øÐмÆË㣻
£¨3£©¸ù¾Ý¼ÓÈÈʱµÄµç¹¦Âʺͱ£ÎÂʱµÄ×ܹ¦ÂÊ£¬ÔËÓõ繦¹«Ê½Çó³öÏûºÄµÄµçÄÜ£®

½â´ð ½â£º
£¨1£©µçѹÁ¦¹øÄÚÆøѹ´ó£¬Ê¹µÄÒºÌåµÄ·Ðµã±ä¸ß£¬ÖóÊìʳƷÓÃʱ½Ï¶Ì£¬ËùÒÔ»á½ÚÔ¼µçÄÜ£»
£¨2£©ÓÉP=UIµÃ£¬I=$\frac{P}{U}$=$\frac{900W}{220V}$¡Ö4.1A£»
ÓÉP=$\frac{{U}^{2}}{R}$µÃ£¬R=$\frac{{U}^{2}}{P}$=$\frac{£¨220V£©^{2}}{900W}$¡Ö53.8¦¸£»
£¨3£©µçѹÁ¦¹ø¼ÓÈÈ20minÏûºÄµÄµçÄÜ£ºW₁=P₁t₁=0.9kW¡Á$\frac{1}{3}$h=0.3kW•h£»
±£ÎÂ10minÏûºÄµÄµçÄÜ£ºW₂=P₂t₂=$\frac{1}{3}$¡Á0.9kW¡Á$\frac{1}{6}$h=0.05kW•h£»
Ôڴ˹ý³ÌÖй²ÏûºÄµÄµçÄÜÊÇW=W₁+W₂=0.3kW•h+0.05kW•h=0.35kW•h£®
´ð£º
£¨1£©·Ðµã£»
£¨2£©ÓõçѹÁ¦¹ø¼ÓÈÈʱ£¬Í¨¹ýµçÈÈË¿µÄµçÁ÷ÊÇ4.1A£¬µçÈÈË¿µÄµç×è¸÷ÊÇ53.8¦¸£»
£¨3£©´Ë¹ý³ÌÖй²ÏûºÄµÄµçÄÜÊÇ0.35kW•h£®

µãÆÀ ±¾ÌâÅжϵçѹÁ¦¹øµÄ¹¤×÷״̬¡¢Çóµç×è¡¢ÏûºÄµÄµçÄÜ£¬·ÖÎöÇå³þµç·½á¹¹£¬¸ù¾Ýµç¹¦Âʹ«Ê½Óëµç¹¦¹«Ê½¼´¿ÉÕýÈ·½âÌ⣮