Question

18£®Ð¡Ã÷ÀûÓÃÍÐÅÌÌìƽºÍÁ¿Í²²âÁ¿ÀÏ´×µÄÃܶȣ®
£¨1£©µ÷½ÚÌìƽʱ£¬ÓÎÂëÒÆÖÁ×ó¶Ë£¬·¢ÏÖÖ¸Õ뾲ֹʱָÔÚ·Ö¶ÈÅÌÖÐÑë¿Ì¶ÈÏßµÄÓҲ࣬ҪʹÌìƽƽºâ£¬ËûÓ¦¸ÃB
A£®°ÑºáÁºÓÒ¶ËÂÝĸÏòÓÒÐý³öһЩ     B£®°ÑºáÁºÓÒ¶ËÂÝĸÏò×óÐý½øһЩ
C£®°ÑÌìƽÓÒÅ̵ÄíÀÂë¼õÉÙһЩ       D£®ÏòÓÒÒƶ¯ÓÎÂë
£¨2£©µ±Ììƽƽºâºó£¬Ð¡Ã÷¿ªÊ¼²âÁ¿£º²âÁ¿²½ÖèÈçͼËùʾ£¬ÕýÈ·µÄ²Ù×÷˳ÐòÊÇ£ºBCA£¨Ìî×Öĸ´úºÅ£©£®

A£®ÓÃÌìƽ²âÁ¿ÉÕ±­ºÍÊ£ÓàÀÏ´×µÄ×ÜÖÊÁ¿£»
B£®½«´ý²âÀÏ´×µ¹ÈëÉÕ±­ÖУ¬ÓÃÌìƽ²â³öÉÕ±­ºÍÀÏ´×µÄ×ÜÖÊÁ¿£»
C£®½«ÉÕ±­ÖÐÀÏ´×µÄÒ»²¿·Öµ¹ÈëÁ¿Í²£¬²â³öÕⲿ·ÖÀÏ´×µÄÌå»ý£»
£¨3£©¸ù¾ÝͼÖÐÊý¾Ý¼ÆËã¿ÉµÃ£ºÀÏ´×µÄÃܶÈÊÇ1.125¡Á10³©K/m³£®

Answer 1

·ÖÎö £¨1£©ÒªÕÆÎÕÌìƽµÄµ÷ƽ£¬¸ù¾ÝÁ½±ßÅ̵ĸߵÍÇé¿ö£¬Æ½ºâÂÝĸҪÏò½Ï¸ßµÄÒ»¶ËÒƶ¯£®
£¨2£©ÕÆÎÕÒºÌåÃܶȵIJâÁ¿¹ý³Ì£¬ÐèÏȲâ³öÒºÌåºÍÉÕ±­µÄ×ÜÖÊÁ¿£¬½«Ò»²¿·ÖÒºÌåµ¹ÈëÁ¿Í²ÖУ¬¶Á³öÁ¿Í²ÖÐÒºÌåµÄÌå»ý£¬²â³öÊ£ÓàÒºÌåºÍÉÕ±­µÄÖÊÁ¿£¬¼ÆËã³öÁ¿Í²ÖÐÒºÌåµÄÖÊÁ¿£¬¸ù¾ÝÃܶȹ«Ê½¼ÆËã³öÒºÌåµÄÃܶȣ®
£¨3£©¶Á³öÉÕ±­ºÍ´×µÄ×ÜÖÊÁ¿¼°Ê£Óà´×ºÍÉÕ±­µÄÖÊÁ¿£¬¶Á³öÁ¿Í²Öд׵ÄÌå»ý£®
ÔÚ¶ÁÊýʱעÒâ±ê³ßµÄ·Ö¶ÈÖµºÍÁ¿Í²µÄ·Ö¶ÈÖµ£®

½â´ð ½â£º£¨1£©Ö¸Õ뾲ֹʱָÔÚ·Ö¶ÈÅÌÖÐÑë¿Ì¶ÈÏßµÄÓҲ࣬ËùÒÔ×óÅ̸ߣ¬Æ½ºâÂÝĸӦÏò×óÒƶ¯£®ÔÚµ÷ƽ¹ý³Ì²»ÄܼӼõíÀÂë»òÒƶ¯ÓÎÂ룮
£¨2£©ÒªÕýÈ·²âÁ¿´×µÄÃܶȣ¬ÐèÏȲâ³öÉÕ±­ºÍÀÏ´×µÄ×ÜÖÊÁ¿£¬½«ÉÕ±­ÖÐÀÏ´×µÄÒ»²¿·Öµ¹ÈëÁ¿Í²£¬²â³öÕⲿ·ÖÀÏ´×µÄÌå»ý£¬ÓÃÌìƽ²âÁ¿ÉÕ±­ºÍÊ£ÓàÀÏ´×µÄ×ÜÖÊÁ¿£®
£¨3£©ÓÉͼ֪£¬ÉÕ±­ºÍÀÏ´×µÄ×ÜÖÊÁ¿m_×Ü=50g+20g+10g+2.4g=82.4g
ÉÕ±­ºÍÊ£ÓàÀÏ´×µÄ×ÜÖÊÁ¿m_Ê£=20g+10g+5g+2.4g=37.4g
Á¿Í²ÖеĴ׵ÄÖÊÁ¿Îªm=m_×Ü-m_Ê£=82.4g-37.4g=45g
´×µÄÌå»ýΪV=40cm³
ËùÒÔ´×µÄÃܶÈΪ¦Ñ=$\frac{m}{V}$=$\frac{45g}{40c{m}^{3}}$=1.125g/cm³=1.125¡Á10³kg/m³£®
¹Ê´ð°¸Îª£º£¨1£©B£»£¨2£©BCA£»£¨3£©1.125¡Á10³£®

µãÆÀ ´ËÌâÊDzâÁ¿ÒºÌåµÄÃܶȣ¬´ËÌ⿼²éÁËÌìƽµÄʹÓúͶÁÊý¼°Á¿Í²µÄ¶ÁÊý¼°ÃܶȵļÆË㣮ҪÕÆÎÕÃܶȵļÆË㹫ʽ£¬ÕÆÎÕ²âÁ¿ÒºÌåÃܶȵķ½·¨£®