Question

11£®ÖÊÁ¿Îªm£¬µçÁ¿ÎªeµÄµç×Ó£¬´ÓËÙ¶ÈΪÁ㣬¾­¹ýÒ»¸öµçѹΪU₁µÄ¼ÓËٵ糡¼ÓËÙºó´¹Ö±½øÈëÒ»¸öƫתµç³¡£¬Æ«×ªµç¼«¼«°å³¤¶ÈΪL£¬Æ«×ªµçѹΪU₂£¬¼«¼ä¾àÀëΪd£®ÔòÏÂÁÐ˵·¨ÖÐÕýÈ·µÄÊÇ£¨¡¡¡¡£©

• A£® µç×ÓÀ뿪¼ÓËٵ糡ʱµÄËÙ¶ÈΪ$\sqrt{\frac{e{U}_{1}}{m}}$
• B£® µç×Ó·ÉԽƫתµç³¡µÄʱ¼äΪ$\sqrt{\frac{m{L}^{2}}{2{U}_{1}}}$
• C£® µç×Ó·ÉԽƫתµç³¡¹ý³ÌÖУ¬¶¯ÄÜÔöÁ¿Îª$\frac{e{{U}_{2}}^{2}{L}^{2}}{4{d}^{2}{U}_{1}}$
• D£® µç×Ó·ÉԽƫתµç³¡¹ý³ÌÖУ¬¶¯Á¿µÄÔöÁ¿ÎªU₂L$\sqrt{\frac{me}{2{U}_{1}{d}^{2}}}$

Answer 1

·ÖÎö ¸ù¾Ý¶¯Äܶ¨ÀíÇó³öµç×ÓÀ뿪¼ÓËٵ糡ʱµÄËٶȣ»½øÈëƫתµç³¡ÖÐ×öÀàƽÅ×Ô˶¯£¬´¹Ö±µç³¡·½ÏòÔÈËÙÔ˶¯£¬Ô˶¯Ê±¼ä$t=\frac{L}{{v}_{0}^{\;}}$£»µç×Ó·ÉԽƫתµç³¡µÄ¹ý³ÌÖУ¬¶¯ÄÜÔöÁ¿µÈÓڵ糡Á¦×öµÄ¹¦£»¶¯Á¿µÄÔöÁ¿µÈÓڵ糡Á¦µÄ³åÁ¿

½â´ð ½â£ºA¡¢ÔÚ¼ÓËٵ糡ÖУ¬¸ù¾Ý¶¯Äܶ¨Àí$e{U}_{1}^{\;}=\frac{1}{2}m{v}_{\;}^{2}$£¬µÃ$v=\sqrt{\frac{2e{U}_{1}^{\;}}{m}}$£¬¹ÊA´íÎó£»
B¡¢µç×ÓÔÚƫתµç³¡ÖÐ×öÀàƽÅ×Ô˶¯£¬Ô˶¯$t=\frac{L}{{v}_{0}^{\;}}=\sqrt{\frac{m{L}_{\;}^{2}}{2e{U}_{1}^{\;}}}$£¬¹ÊB´íÎó£»
C¡¢µç×ÓÔÚƫתµç³¡ÖеIJàÒÆ$y=\frac{1}{2}a{t}_{\;}^{2}=\frac{1}{2}\frac{e{U}_{2}^{\;}}{md}£¨\frac{L}{{v}_{0}^{\;}}£©_{\;}^{2}$=$\frac{{U}_{2}^{\;}{L}_{\;}^{2}}{4d{U}_{1}^{\;}}$£¬µç³¡Á¦$F=eE=e\frac{{U}_{2}^{\;}}{d}$£¬¸ù¾Ý¶¯Äܶ¨Àí$¡÷{E}_{k}^{\;}=Fy=\frac{e{U}_{2}^{2}{L}_{\;}^{2}}{4d{U}_{1}^{\;}}$£¬¹ÊCÕýÈ·£»
D¡¢¸ù¾Ý¶¯Á¿¶¨Àí¡÷p=I=Ft=$eEt=e\frac{{U}_{2}^{\;}}{d}\sqrt{\frac{m{L}_{\;}^{2}}{2e{U}_{1}^{\;}}}={U}_{2}^{\;}L\sqrt{\frac{me}{2{U}_{1}^{\;}{d}_{\;}^{2}}}$£¬¹ÊDÕýÈ·£»
¹ÊÑ¡£ºCD

µãÆÀ ±¾ÌâÊÇ´øµçÁ£×ÓÏȼÓËÙºóƫתÎÊÌ⣬µç³¡ÖмÓËÙ¸ù¾Ý¶¯Äܶ¨ÀíÇó½â»ñµÃµÄËٶȡ¢Æ«×ªµç³¡ÖÐÀàƽÅ×Ô˶¯µÄÑо¿·½·¨ÊÇÔ˶¯µÄ·Ö½âºÍºÏ³É£¬³£¹æÎÊÌ⣮