DIV.MyFav_1193109006691 P.MsoNormal{TEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; MARGIN: 0cm 0cm 0pt; FONT-FAMILY: "Times New Roman"; TEXT-ALIGN: justify}DIV.MyFav_1193109006691 LI.MsoNormal{TEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; MARGIN: 0cm 0cm 0pt; FONT-FAMILY: "Times New Roman"; TEXT-ALIGN: justify}DIV.MyFav_1193109006691 DIV.MsoNormal{TEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; MARGIN: 0cm 0cm 0pt; FONT-FAMILY: "Times New Roman"; TEXT-ALIGN: justify}DIV.MyFav_1193109006691 P.MsoHeader{BORDER-RIGHT: medium none; PADDING-RIGHT: 0cm; BORDER-TOP: medium none; PADDING-LEFT: 0cm; FONT-SIZE: 9pt; PADDING-BOTTOM: 0cm; MARGIN: 0cm 0cm 0pt; BORDER-LEFT: medium none; LAYOUT-GRID-MODE: char; PADDING-TOP: 0cm; BORDER-BOTTOM: medium none; FONT-FAMILY: "Times New Roman"; TEXT-ALIGN: center}DIV.MyFav_1193109006691 LI.MsoHeader{BORDER-RIGHT: medium none; PADDING-RIGHT: 0cm; BORDER-TOP: medium none; PADDING-LEFT: 0cm; FONT-SIZE: 9pt; PADDING-BOTTOM: 0cm; MARGIN: 0cm 0cm 0pt; BORDER-LEFT: medium none; LAYOUT-GRID-MODE: char; PADDING-TOP: 0cm; BORDER-BOTTOM: medium none; FONT-FAMILY: "Times New Roman"; TEXT-ALIGN: center}DIV.MyFav_1193109006691 DIV.MsoHeader{BORDER-RIGHT: medium none; PADDING-RIGHT: 0cm; BORDER-TOP: medium none; PADDING-LEFT: 0cm; FONT-SIZE: 9pt; PADDING-BOTTOM: 0cm; MARGIN: 0cm 0cm 0pt; BORDER-LEFT: medium none; LAYOUT-GRID-MODE: char; PADDING-TOP: 0cm; BORDER-BOTTOM: medium none; FONT-FAMILY: "Times New Roman"; TEXT-ALIGN: center}DIV.MyFav_1193109006691 P.MsoFooter{FONT-SIZE: 9pt; MARGIN: 0cm 0cm 0pt; LAYOUT-GRID-MODE: char; FONT-FAMILY: "Times New Roman"}DIV.MyFav_1193109006691 LI.MsoFooter{FONT-SIZE: 9pt; MARGIN: 0cm 0cm 0pt; LAYOUT-GRID-MODE: char; FONT-FAMILY: "Times New Roman"}DIV.MyFav_1193109006691 DIV.MsoFooter{FONT-SIZE: 9pt; MARGIN: 0cm 0cm 0pt; LAYOUT-GRID-MODE: char; FONT-FAMILY: "Times New Roman"}DIV.MyFav_1193109006691 P.MsoBodyTextIndent{TEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 11.35pt; FONT-FAMILY: "Times New Roman"; TEXT-ALIGN: justify}DIV.MyFav_1193109006691 LI.MsoBodyTextIndent{TEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 11.35pt; FONT-FAMILY: "Times New Roman"; TEXT-ALIGN: justify}DIV.MyFav_1193109006691 DIV.MsoBodyTextIndent{TEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 11.35pt; FONT-FAMILY: "Times New Roman"; TEXT-ALIGN: justify}DIV.MyFav_1193109006691 A:link{COLOR: blue; TEXT-DECORATION: underline}DIV.MyFav_1193109006691 SPAN.MsoHyperlink{COLOR: blue; TEXT-DECORATION: underline}DIV.MyFav_1193109006691 A:visited{COLOR: purple; TEXT-DECORATION: underline}DIV.MyFav_1193109006691 SPAN.MsoHyperlinkFollowed{COLOR: purple; TEXT-DECORATION: underline}DIV.MyFav_1193109006691 P{FONT-SIZE: 12pt; MARGIN-LEFT: 0cm; MARGIN-RIGHT: 0cm; FONT-FAMILY: 宋体}DIV.MyFav_1193109006691 DIV.Section1{page: Section1}DIV.MyFav_1193109006691 OL{MARGIN-BOTTOM: 0cm}DIV.MyFav_1193109006691 UL{MARGIN-BOTTOM: 0cm} 14.B 15.A 16.AC 17.C 18.C 19.AD 20.B 21.D 22.(1)①竖直位移或↑↓ 衰减或衰减调节 y增益 ②扫描范围 1k挡位 扫描微调 (2)①P点是在实验的第一步中小球1落点的平均位置 M点是小球1与小球2碰后小球1落点的平均位置 N点是小球2落点的平均位置 ②小球从槽口C飞出后作平抛运动的时间相同,假设为t,则有 小球2碰撞前静止,即 ③OP与小球的质量无关,OM和ON与小的质量有关 23.解:(1)设经过时间t,甲追上乙,则根据题意有vt-vt/2=13.5 将v=9代入得到:t=3s, 再有 v=at 解得:a=3m/s2 (2)在追上乙的时候,乙走的距离为s, 则:s=at2/2 代入数据得到 s=13.5m 所以乙离接力区末端的距离为?s=20-13.5=6.5m 24.解:设:小球m的摆线长度为l 小球m在下落过程中与M相碰之前满足机械能守恒: ① m和M碰撞过程满足: ② ③ 联立 ②③得: ④ 说明小球被反弹,而后小球又以反弹速度和小球M发生碰撞,满足: ⑤ ⑥ 解得: ⑦ 整理得: ⑧ 所以: ⑨ 而偏离方向为450的临界速度满足: ⑩ 联立① ⑨ ⑩代入数据解得,当n=2时, 当n=3时, 所以,最多碰撞3次 25.解:对于y轴上的光屏亮线范围的临界条件如图1所示:带电粒子的轨迹和x=a相切,此时r=a,y轴上的最高点为y=2r=2a ; 对于x轴上光屏亮线范围的临界条件如图2所示:左边界的极限情况还是和x=a相切,此刻,带电粒子在右边的轨迹是个圆,由几何知识得到在x轴上的坐标为x=2a;速度最大的粒子是如图2中的实线,又两段圆弧组成,圆心分别是c和c’。由对称性得到c’在x轴上,设在左右两部分磁场中运动时间分别为t1和t2,满足 解得 由数学关系得到: 代入数据得到: 所以在x 轴上的范围是