Question

17£®Èçͼ¼×ËùʾÊÇ´òÀÌ´¬Éϵĵ綯»úºÍÀ¿Éþ´ÓË®µ×ÊúÖ±´òÀÌÒ»ÖØΪ30000NµÄ³¤·½ÌåÎïÌ壬ͨ¹ý´òÀÌ´¬µÄ³ÔË®Ï߱仯²âµÃ£¬µ±ÎïÌåÍêÈ«½þûÔÚʼÖÕʱÊܵ½µÄ¸¡Á¦Îª10000N£¬ÈçͼÒÒºá×ø±êΪ´òÀÌʱ¼ä£¬×Ý×ø±êΪ´òÀÌ»ú¶ÔÎïÌåµÄÀ­Á¦£¬Èç¹û±»´òÀ̵ÄÎïÌåʼÖÕÒÔ0.1m/sµÄËÙ¶ÈÔÈËÙÉÏÉý£¬gÈ¡10N/kg£®Çó£º
£¨1£©Í¼ÖÐX¡¢YµÄÖµ·Ö±ðΪ20000N¡¢30000N£®
£¨2£©ÔÚË®ÖдòÀÌÎïÌåʱ£¨Î´Â¶³öË®Ã棩£¬´òÀÌ»ú¶ÔÎïÌåËù×öµÄ¹¦£»
£¨3£©Èç¹ûµç¶¯»úµÄ¶î¶¨µçѹΪ220V£¬´Ë×°ÖÃ×ܵÄת»¯Ð§ÂÊΪ80%£¬Í¨¹ý¼ÆË㣬ÇëÄãÔÚÏÂÃ漸ÖÖµçÀÂÖÐÑ¡ÔñºÏÊʵĵçÀ£»

µçÀÂ	µçÀÂA	µçÀÂB	µçÀÂC	µçÀÂD
¹æ¸ñ	10A	15A	20A	25A

Answer 1

·ÖÎö £¨1£©ÒÑÖªÎïÌåÖØÁ¦Îª30000N£¬µ±ÎïÌåÍêÈ«½þûÔÚʼÖÕʱÊܵ½µÄ¸¡Á¦Îª10000N£¬¾Ý´Ë¿ÉÇóµÃÀ­Á¦F£¬¼´XµÄÖµ£»µ±ÎïÌåÈ«²¿Â¶³öË®Ã棬´ËʱµÄÀ­Á¦µÈÓÚÆäÖØÁ¦£¬¼´¿ÉÖªYµÄÖµ£»
£¨2£©ÒÑÖªÎïÌåʼÖÕÒÔ0.1m/sµÄËÙ¶ÈÔÈËÙÉÏÉý£¬ËùÓÃʱ¼äΪ10s£¬ÓÉ´Ë¿ÉÇóµÃÎïÌåÉÏÉýµÄ¾àÀ룬ÒÑÖªÔÚË®ÖдòÀÌÎïÌåʱµÄÀ­Á¦£¬È»ºóÀûÓÃW=Fs¿ÉÇóµÃ´òÀÌ»ú¶ÔÎïÌåËù×öµÄ¹¦£»
£¨3£©¸ù¾ÝP=$\frac{W}{t}$=$\frac{Fs}{t}$=FvÇóµÃ¹¦ÂÊ£¬¸ù¾Ýµç¶¯»úµçÄÜת»»Îª»úеÄܵÄЧÂÊΪ80%£¬ÔÙÀûÓÃP=UI¿ÉÇóµÃµç¶¯»úÏßȦÖеçÁ÷µÄ´óС£¬È»ºó¿´×ö³öÑ¡Ôñ£®

½â´ð ½â£º£¨1£©ÓÉͼÏó¿ÉÖª£¬Ç°50sÄÚÎïÌå½þÔÚË®ÖУ¬´ËʱÀ­Á¦F=G-F_¸¡=30000N-10000N=20000N£¬¼´XµÄֵΪ20000N£»
µ±ÎïÌåÈ«²¿Â¶³öË®Ã棬´ËʱµÄÀ­Á¦µÈÓÚÆäÖØÁ¦£¬¼´YµÄֵΪ30000N£»
£¨2£©ÓÉv=$\frac{s}{t}$¿ÉµÃ£¬ÎïÌåÉÏÉýµÄ¾àÀës=vt=0.1m/s¡Á10s=1m£¬
Ôò´òÀÌ»ú¶ÔÎïÌåËù×öµÄ¹¦W=Fs=20000N¡Á1m=20000J£®
£¨3£©ÓÉP=$\frac{W}{t}$=$\frac{Fs}{t}$=Fv¿ÉµÃ£¬P=Fv=20000N¡Á0.1m/s=2000W
µç¶¯»úµçÄÜת»»Îª»úеÄܵÄЧÂÊΪ80%£¬
¼´¦Ç=$\frac{{W}_{»úе}}{{W}_{µç}}$=$\frac{{P}_{»úе}t}{{P}_{µç}t}$=80%£¬µÃ£ºP_µç¡Á80%=2000W£¬
½âµÃP_µç=2500W£¬
ÒòΪP=UI£¬
ËùÒÔI=$\frac{{P}_{µç}}{U}$=$\frac{2500W}{220V}$¡Ö11.36A£®
ÓɱíÖеçÀ¹æ¸ñ¿ÉÖª£¬Ñ¡ÔñµçÀÂB±È½ÏºÏÊÊ£®
´ð£º£¨1£©20000N£»30000N£»
£¨2£©ÔÚË®ÖдòÀÌÎïÌåʱ£¨Î´Â¶³öË®Ã棩£¬´òÀÌ»ú¶ÔÎïÌåËù×öµÄ¹¦Îª20000J£»
£¨3£©Ñ¡ÔñµçÀÂB±È½ÏºÏÊÊ£®

µãÆÀ ±¾Ì⿼²éÁËËٶȹ«Ê½¼°ÆäÓ¦Óᢰ¢»ùÃ×µÂÔ­ÀíºÍµç¹¦ÂÊÓëµçѹ¡¢µçÁ÷µÄ¹Øϵ£¬¹Ø¼üÊÇ»á·ÖÎöµç¶¯»úµÄ»úеÊä³ö¹¦ÂÊËæʱ¼ä±ä»¯µÄͼÏóµÃ³öÏà¹ØµÄÐÅÏ¢£¬Òª×¢Òâ¸ù¾ÝP=FvÇó³öÉþ×ÓµÄÀ­Á¦£¬±¾Ìâ±È½Ï¸´ÔÓ£¬ÊôÓÚÄÑÌ⣬½âÌâ¹ý³ÌÖÐÒ»¶¨Òª×ÐϸÈÏÕ森