ÌâÄ¿ÄÚÈÝ
ÈçÌâl2-1ͼËùʾ£¬ÖÊÁ¿Îª60kgµÄÏû·À¶ÓÔ±´ÓÒ»¸ù¹Ì¶¨µÄÊúÖ±½ðÊô¸ËÉÏÓɾ²Ö¹»¬Ï£¬¾¹ý2.5sʱ¼äÂäµ½µØÃæÉÏ£®Ï»¬ÖÐÏû·À¶ÓÔ±Êܵ½µÄÊúÖ±ÏòÉϵÄĦ²ÁÁ¦ËæÊ±¼ä±ä»¯µÄÇé¿öÈçÌâl2-2ͼËùʾ£¬È¡g=10m/s2£®Çó£º
(1)Ïû·À¶ÓԱϻ¬¹ý³ÌÖеļÓËÙ¶È£»
(2)Ïû·À¶ÓÔ±¿ªÊ¼Ï»¬Ê±ÀëµØÃæµÄ¸ß¶È£»
(3)Ïû·À¶ÓԱϻ¬¹ý³ÌÖÐĦ²ÁÁ¦¶ÔËûËù×öµÄ¹¦£®
![]()
½â£º(1)ÓÉÅ£¶ÙµÚ¶þ¶¨ÂɵÃ
¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡(2·Ö)
=5.0¡Á10-2m¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡(1·Ö)
(2)ÈçͼËùʾ£¬ÉèÁ£×ÓµÄÔ˶¯¹ì¼£Ç¡Óëµ²°åÏàÇУ¬Óɼ¸ºÎ¹ØÏµµÃ£º
¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡(2·Ö)
X0=7.5¡Á10-2m¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡(1·Ö)
Ϊʹ¸ÃÁ£×Ó²»´òµ½µ²°åÉÏ£¬x0¡Ý7.5¡Á10-2m¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡(1·Ö)
Á£×ÓÔڴų¡ÖÐÔ˶¯µÄÖÜÆÚΪT
T=
=
=
¡Á10-7s¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡(1·Ö)
¸ÃÁ£×ÓÔڴų¡ÖÐÔ˶¯µÄʱ¼ä
=
=
¡¡¡¡¡¡¡¡(1·Ö)
(3)Èôx0=5.0¡Á10-2m£¬Ôòx0=R
µ±Á£×ÓÑØ×Å£y·½ÏòÈëÉäʱ£¬½«´òÔÚµ²°åÉϵÄAµã
Æä×Ý×ø±êyA=£R=500¡Á10-2m¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡(2·Ö)
µ±Á£×ÓÑØ×Å+x·½ÏòÈëÉäʱ£¬Á£×ÓµÄÔ˶¯¹ì¼£Ç¡ºÃÓëµ²°åÏàÇÐÓÚBµã
Æä×Ý×ø±êyB=R=5.0¡Á10-2m¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡(2·Ö)
ÔòÁ£×Ó´òÔÚµ²°åÉϵķ¶Î§Îª-500¡Á10-2m¡Üy<5.0¡Á10-2m¡¡¡¡¡¡¡(1·Ö)
Á£×ÓÔڴų¡ÖÐËùÄܵ½´ïµÄÇøÓòÈçͼËùʾ¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡(4·Ö)
![]()
![]()