ÌâÄ¿ÄÚÈÝ
10£®![](http://thumb.1010pic.com/pic3/quiz/images/201705/120/74284901.png)
£¨1£©Ð¡Çòµ½´ï¹ìµÀ×îµÍµãBʱµÄËٶȴóСvB=1.94m/s£¬µ±µØµÄÖØÁ¦¼ÓËÙ¶Èg=9.70m/s2£»£¨½á¹û¾ùÈ¡ÈýλÓÐЧÊý×Ö£©£®
£¨2£©Ð¡ÇòÔÚÔ²»¡²Û¹ìµÀÉÏÊÇ·ñÊܵ½ÁËĦ²ÁÁ¦£ºÊܵ½£¨Ìî¡°Êܵ½¡±¡¢¡°Î´Êܵ½¡±»ò¡°Ìõ¼þ²»×㣬ÎÞ·¨È·¶¨¡±£©£®
·ÖÎö £¨1£©¸ù¾ÝˮƽλÒƺÍʱ¼ä¼ä¸ôÇó³öСÇòµ½´ï×îµÍµãBµÄËٶȣ¬¼´Æ½Å×Ô˶¯µÄ³õËٶȣ®¸ù¾ÝÊúÖ±·½ÏòÉÏÁ¬ÐøÏàµÈʱ¼äÄÚµÄλÒÆÖ®²îÊÇÒ»ºãÁ¿Çó³öµ±µØµÄÖØÁ¦¼ÓËٶȣ®
£¨2£©ÈôÎÞĦ²ÁÁ¦£¬¸ù¾Ý¶¯Äܶ¨ÀíÇó³ö×îµÍµãµÄËٶȣ¬Í¨¹ý±È½ÏÅжÏСÇòÔÚÔ²»¡¹ìµÀÉÏÊÇ·ñÊܵ½Ä¦²ÁÁ¦£®
½â´ð ½â£º£¨1£©Ð¡Çò×îµÍµãBµÄËٶȵÈÓÚƽÅ×Ô˶¯µÄ³õËٶȣ¬ÔòÓУº
${v}_{B}=\frac{4L}{T}=\frac{4¡Á4.85¡Á1{0}^{-2}}{0.1}m/s$=1.94m/s£®
ÔÚÊúÖ±·½ÏòÉÏ£¬¸ù¾Ý¡÷y=2L=gT2µÃ£º
g=$\frac{2L}{{T}^{2}}=\frac{2¡Á4.85¡Á1{0}^{-2}}{0.01}m/{s}^{2}=9.70m/{s}^{2}$£®
£¨2£©ÈôСÇòÓëÔ²»¡¹ìµÀûÓÐĦ²Á£¬¸ù¾Ý¶¯Äܶ¨ÀíµÃ£º$mgR=\frac{1}{2}m{{v}_{B}}^{2}$
½âµÃ£º${v}_{B}=\sqrt{2gR}=\sqrt{2¡Á9.7¡Á0.25}$m/s¡Ö2.20m/s£¾1.94m/s£¬¿É֪СÇòÔÚÔ²»¡¹ìµÀÉÏÊܵ½ÁËĦ²ÁÁ¦£®
¹Ê´ð°¸Îª£º£¨1£©1.94£¬9.70£º£»£¨2£©Êܵ½
µãÆÀ ½â¾ö±¾ÌâµÄ¹Ø¼üÖªµÀƽÅ×Ô˶¯ÔÚˮƽ·½ÏòºÍÊúÖ±·½ÏòÉϵÄÔ˶¯¹æÂÉ£¬½áºÏÔ˶¯Ñ§¹«Ê½Áé»îÇó½â£¬ÄѶȲ»´ó£®
![](http://thumb2018.1010pic.com/images/loading.gif)
![](http://thumb.1010pic.com/pic3/quiz/images/201703/68/be8b8b2b.png)
A£® | Á£×ÓÔÚƽÐнðÊô°å¼äµÄÔ˶¯Ê±¼äºÍ½ðÊô°åÓҶ˵½¹âÆÁµÄÔ˶¯Ê±¼äÏàµÈ | |
B£® | °å¼äµç³¡Ç¿¶È´óСΪ$\frac{2mg}{q}$ | |
C£® | Èô½ö½«»¬Æ¬PÏòÏ»¬¶¯Ò»¶Îºó£¬ÔÙÈøÃÖʵã´ÓNµãÒÔˮƽËÙ¶Èv0ÉäÈë°å¼ä£¬Öʵ㲻»á´¹Ö±´òÔÚ¹âÆÁÉÏ | |
D£® | Èô½ö½«Á½Æ½ÐаåµÄ¼ä¾à±ä´óһЩ£¬ÔÙÈøÃÖʵã´ÓNµãÒÔˮƽËÙ¶Èv0ÉäÈë°å¼ä£¬ÖʵãÒÀÈ»»á´¹Ö±´òÔÚ¹âÆÁÉÏ |
![](http://thumb.1010pic.com/pic3/quiz/images/201505/49/6f5d9b98.png)
A£® | µçÁ÷±íAµÄʾÊýÔö´ó | B£® | µçѹ±íV1µÄʾÊýÔö´ó | ||
C£® | µçѹ±íV2µÄʾÊý¼õС | D£® | ¡÷U1´óÓÚ¡÷U2 |
A£® | $\frac{3¦Ð}{G{T}^{2}£¨1-k£©}$ | B£® | $\frac{3k¦Ð}{G{T}^{2}£¨1-k£©}$ | C£® | $\frac{3¦Ð£¨1-k£©}{G{T}^{2}}$ | D£® | $\frac{3¦Ð£¨1-k£©}{kG{T}^{2}}$ |
A£® | »¬¶¯Ä¦²ÁÁ¦¿ÉÄܶÔÎïÌå×ö¸º¹¦£¬¿ÉÄÜ×öÕý¹¦£¬Ò²¿ÉÄܲ»×ö¹¦ | |
B£® | »¬¶¯Ä¦²ÁÁ¦¶ÔÎïÌå×ÜÊÇ×ö¸º¹¦ | |
C£® | ¾²Ä¦²ÁÁ¦¶ÔÎïÌå×ÜÊDz»×ö¹¦ | |
D£® | Á¦¶ÔÎïÌå×ö¹¦¶à£¬ËµÃ÷ÎïÌåµÄλÒÆÒ»¶¨´ó |
A£® | ͨ¹ýÏßȦµÄ´ÅͨÁ¿±ä»¯ÂÊ´ïµ½×î´óÖµ | |
B£® | ÏßȦƽÃæÓë´Å¸ÐÏß·½Ïò´¹Ö± | |
C£® | ͨ¹ýÏßȦµÄ´ÅͨÁ¿´ïµ½×î´óÖµ | |
D£® | ÏßȦÖеĸÐÓ¦µç¶¯ÊÆΪÁã |
![](http://thumb.1010pic.com/pic3/quiz/images/201705/237/03e04d92.png)
A£® | pA¡ä=3 kg•m/s pB¡ä=4 kg•m/s | |
B£® | pA¡ä=-2kg•m/s pB¡ä=7 kg•m/s | |
C£® | pA¡ä=3 kg•m/s pB¡ä=2 kg•m/s | |
D£® | pA¡ä=1 kg•m/s pB¡ä=4 kg•m/s |
![](http://thumb.1010pic.com/pic3/quiz/images/201612/173/cca36990.png)
A£® | Ïß¿ò½øÈëÇøÓòIʱÓëÀ뿪ÇøÓòIʱµÄµçÁ÷·½ÏòÏàͬ | |
B£® | Ïß¿ò½øÈëÇøÓò¢òʱÓëÀ뿪ÇøÓò¢òʱËùÊÜ°²ÅàÁ¦µÄ·½ÏòÏàͬ | |
C£® | Ïß¿òÓпÉÄÜÔÈËÙͨ¹ý´Å³¡ÇøÓòI | |
D£® | Ïß¿òͨ¹ýÇøÓòIºÍÇøÓò¢ò²úÉúµÄ×ÜÈÈÁ¿ÎªQ=mg£¨d+h£© |