Question

2£® 2015ÄêÎåһС³¤¼Ù£¬ÌƺÓijÆïÐоãÀÖ²¿×éÖ¯»áÔ±£¬ÆïÐÐʯÖùɽ·ç¾°Çø£®Í¼ÖеÄɽµØ×ÔÐгµÊÇÌåÖØ70kgµÄ»áÔ±ÀîΰµÄÆïÐÐÓ󵣬ÆäÏà¹ØÊý¾Ý¼ûÏÂ±í£º

³µ¼Ü²ÄÁÏ	̼ÏËά
³µ¼Ü²ÄÁÏÌå»ý/cm2	2500
³µ¼ÜÖÊÁ¿/kg	4.5
Õû³µÖÊÁ¿/kg	10
µ¥ÂÖ½ÓµØÃæ»ý/cm2	4

£¨1£©É½µØ×ÔÐгµµÄÂÖ×Ó±ÈÆÕͨ×ÔÐгµÒª´Ö£¬ÊÇΪÁËÔö´óÊÜÁ¦Ãæ»ý£¬¼õСѹǿ£®³µÊÖÒ»°ãÔÚÉÏÆÂǮҪ¼Ó½ôµÇ¼¸Ï³µ×Ó¼Ó´ó³µËÙ£¬ÕâÊÇΪÁËÔö´ó¶¯ÄÜ£¬ÉÏÆÂʱ¿Éת»¯Îª½Ï¶àµÄÖØÁ¦ÊÆÄÜ£¬ÈÝÒ×ÉÏÆ£®
£¨2£©Çó̼ÏËά³µ¼ÜµÄÃܶȣ»
£¨3£©ÆïÐÐÖеÄɽµØ×ÔÐгµ¶ÔµØÃæµÄѹǿ£»
£¨4£©ÀîΰÔÚij±µ°ÔÈËÙÆïÐÐ6km£¬ºÄʱ10min£®Èô¸Ã·¶Î×èÁ¦Îª×ÜÖØÁ¦µÄ0.32±¶£¬ÇóËûµÄÆïÐй¦ÂÊ£®

Answer 1

·ÖÎö £¨1£©¼õСѹǿµÄ·½·¨£ºÔÚѹÁ¦Ò»¶¨Ê±£¬Ôö´óÊÜÁ¦Ãæ»ýÀ´¼õСѹǿ£®ÔÚÊÜÁ¦Ãæ»ýÒ»¶¨Ê±£¬¼õСѹÁ¦À´¼õСѹǿ£®
ÎïÌåµÄ¶¯ÄÜ´óСÓÉÎïÌåµÄÖÊÁ¿ºÍÎïÌåµÄËÙ¶ÈÁ½¸öÒòËؾö¶¨£¬²¢ÇÒÖÊÁ¿Ô½´ó£¬ËÙ¶ÈÔ½´ó£¬ÎïÌåµÄ¶¯ÄܾÍÔ½´ó£®
£¨2£©´Ó±íÖÐÊý¾Ý¿É֪̼ÏËά³µ¼ÜµÄÖÊÁ¿ºÍÌå»ý£¬ÀûÓÃÃܶȹ«Ê½¼´¿ÉÇóµÃÆäÃܶȣ»
£¨3£©µØÃæËùÊܵÄѹÁ¦µÈÓÚ³µ×ÓºÍÔ˶¯Ô±µÄÖØÁ¦£¬¸ù¾Ý¹«Ê½p=$\frac{F}{S}$¿ÉÇóµØÃæÊܵ½µÄѹǿ£®
£¨4£©¸ù¾ÝÔ˶¯Ô±Æï×ÅÒ»Á¾É½µØ×ÔÐгµÔÚƽֱ¹«Â·ÉÏÔÈËÙÐÐÊ»£¬ÏÈÅжϳöÔ˶¯Ô±¿Ë·þ×èÁ¦Ëù×öµÄ¹¦W£¬ÔÙÓù«Ê½P=$\frac{W}{t}$Ëã³öÀîΰµÄ¹¦ÂÊ£®

½â´ð ½â£º£¨1£©É½µØ×ÔÐгµµÄÂÖ×Ó±ÈÆÕͨ×ÔÐгµÒª´Ö£¬ÊÇÔÚѹÁ¦Ò»¶¨Ê±£¬Ôö´óÊÜÁ¦Ãæ»ý¼õС³µ¶ÔµØÃæµÄѹǿ£®
ÔÚÉÏÆÂÇ°¼Ó½ôµÅ¼¸Ï£¬ÊÇΪÁË»ñµÃ¸ü´óµÄ³µËÙ£¬´Ó¶ø»á»ñµÃ¸ü´óµÄ¶¯ÄÜ£¬µ±³µÁ¾ÉÏÆÂʱ£¬¾Í»áÓиü¶àµÄ¶¯ÄÜת»¯ÎªÖØÁ¦ÊÆÄÜ£¬×ÔÐгµ¾ÍÉϵÃÔ½¸ß£¬³µ¾ÍÈÝÒ×ÉÏÆ£»
£¨2£©Ì¼ÏËά³µ¼ÜµÄÃܶÈ
¦Ñ=$\frac{m}{V}$=$\frac{4.5kg}{2.5¡Á1{0}^{-3}{m}^{3}}$=1.8¡Á10³ kg/m³£¬
£¨3£©µØÃæËùÊܵÄѹÁ¦
F=G=mg=£¨10kg+70kg£©¡Á10N/kg=800N£¬
×ÔÐгµ¶ÔµØÃæµÄѹǿ
P=$\frac{F}{S}$=$\frac{800N}{4¡Á2¡Á1{0}^{-4}{m}^{2}}$=1¡Á10⁶ pa£¬
£¨4£©×ÔÐгµ¿Ë·þ×èÁ¦×öµÄ¹¦
W=fs=0.02GS=0.02¡Á800N¡Á6¡Á10³m=9.6¡Á10⁴J£¬
ÆïÐй¦ÂÊ
P=$\frac{W}{t}$=$\frac{9.6¡Á1{0}^{4}J}{10¡Á60s}$=160W£®
¹Ê´ð°¸Îª£º£¨1£©Ôö´óÊÜÁ¦Ãæ»ý£¬¼õСѹǿ£»Ôö´ó¶¯ÄÜ£¬ÉÏÆÂʱ¿Éת»¯Îª½Ï¶àµÄÖØÁ¦ÊÆÄÜ£¬ÈÝÒ×ÉÏÆ£»
£¨2£©Ì¼ÏËά³µ¼ÜµÄÃܶÈ1.8¡Á10³kg/m³£»
£¨3£©±ÈÈüÖеÄɽµØ×ÔÐгµ¶ÔµØÃæµÄѹǿ1¡Á10⁶Pa£»
£¨4£©ËûµÄÆïÐй¦ÂÊ160W£®

µãÆÀ ±¾Ì⿼²éÖÊÁ¿¡¢ÖØÁ¦¡¢Ñ¹Á¦¡¢Ñ¹Ç¿µÄ¼ÆË㣬¹Ø¼üÊǹ«Ê½¼°Æä±äÐεÄÁé»îÔËÓã¬ÒªÖªµÀÔÚˮƽÃæÉÏÎïÌå¶ÔˮƽÃæµÄѹÁ¦µÈÓÚÎïÌå×ÔÉíµÄÖØÁ¦£¬½âÌâ¹ý³ÌÖÐҪעÒⵥλµÄ»»Ë㣮»¹ÒªÖªµÀ´Ó±íÖÐÌáÈ¡ÓÐÓõÄÐÅÏ¢£®