Question

15£®ÈçͼËùʾ£¬abcÊǹ⻬µÄ¹ìµÀ£¬ÆäÖÐabÊÇˮƽµÄ£¬bcΪÓëabÏàÇеÄλÓÚÊúֱƽÃæÄڵİëÔ²£¬°ë¾¶R=0.30m£®ÖÊÁ¿m=0.20kgµÄСÇòA¾²Ö¹ÔÚ¹ìµÀÉÏ£¬ÁíÒ»ÖÊÁ¿M=0.60kg¡¢ËÙ¶Èv₀=5.5m/sµÄСÇòBÓëСÇòAÕýÅö£®ÒÑÖªÏàÅöºóСÇòA¾­¹ý°ëÔ²µÄ×î¸ßµãcÂäµ½¹ìµÀÉϾàbµãΪL=4$\sqrt{2}$R´¦£¬ÖØÁ¦¼ÓËÙ¶Èg=10m/s²£¬Çó£º
£¨1£©Åöײ½áÊøºó£¬Ð¡ÇòAËٶȵĴóС£»
£¨2£©ÅöײºóBÇòµÄËٶȣ»
£¨3£©ÇóÅöײ¹ý³ÌÖÐËðʧµÄ»úеÄÜ£®

Answer 1

·ÖÎö £¨1¡¢2£©¸ù¾ÝƽÅ×Ô˶¯µÄ¹æÂÉ£¬Çó³öAÇòÔÚCµãµÄËٶȣ¬¸ù¾Ý»úеÄÜÊغ㶨ÂÉÇó³öAÇòÅöºóµÄËٶȣ¬¸ù¾Ý¶¯Á¿Êغ㶨ÂÉÇó³öBÇòÅöºóµÄËٶȣ»
£¨3£©¸ù¾ÝÄÜÁ¿Êغ㶨ÂÉÁÐʽÇó½âÅöײ¹ý³ÌÖÐËðʧµÄ»úеÄÜ£®

½â´ð ½â£º£¨1¡¢2£©·Ö±ðÒÔv₁ºÍv₂±íʾСÇòAºÍBÅöºóµÄËٶȣ¬v₃±íʾСÇòAÔÚ°ëÔ²×î¸ßµãµÄËٶȣ¬Ôò¶ÔAÓÉƽÅ×Ô˶¯¹æÂÉÓУ¬
ˮƽ·½Ïò£ºL=v₃t=4$\sqrt{2}$R
ÊúÖ±·½Ïò£ºh=2R=$\frac{1}{2}$gt²
½âµÃ£ºv₃=2$\sqrt{6}$m/s£®
¶ÔAÔËÓûúеÄÜÊغ㶨Âɵãº
$\frac{1}{2}$mv₁²=2mgR+$\frac{1}{2}$mv₃²
ÒÔAºÍBΪϵͳ£¬¹æ¶¨ÏòÓÒΪÕý·½Ïò£¬Åöײǰºó¶¯Á¿Êغ㣺
Mv₀=Mv₂+mv₁
ÁªÁ¢½âµÃ£ºv₁=6m/s£¬v₂=3.5m/s£®
£¨3£©¸ù¾ÝÄÜÁ¿Êغ㶨ÂÉ¿ÉÖª£¬
Åöײ¹ý³ÌÖÐËðʧµÄ»úеÄÜ$¡÷E=\frac{1}{2}M{{v}_{0}}^{2}-\frac{1}{2}M{{v}_{1}}^{2}-\frac{1}{2}m{{v}_{2}}^{2}$=1.8J
´ð£º£¨1£©Åöײ½áÊøºó£¬Ð¡ÇòAËٶȵĴóСΪ6m/s£»
£¨2£©ÅöײºóBÇòµÄËÙ¶ÈΪ3.5m/s£»
£¨3£©Åöײ¹ý³ÌÖÐËðʧµÄ»úеÄÜΪ1.8J£®

µãÆÀ ±¾Ì⿼²éÁ˶¯Á¿Êغ㶨ÂÉ¡¢»úеÄÜÊغ㶨ÂÉ¡¢Æ½Å×Ô˶¯µÈ¹æÂÉ£¬×ÛºÏÐÔ½ÏÇ¿£¬ÐèÔÚƽʱµÄѧϰÖмÓǿѵÁ·£®¶ÔÓÚƽÅ×Ô˶¯µÄÎÊÌâÎÒÃǵÄ˼·ÊǷֽ⣬´Óˮƽ·½ÏòºÍÊúÖ±·½ÏòÈ¥Ñо¿£®