2024~2025学年第一学期高二年级期末学业诊断
物理参考答案及评分建议
一、单项选择题:本题包含 7小题,每小题 4分,共 28分。
题号 1 2 3 4 5 6 7
选项 C C C D C C B
二、多项选择题:本题包含 3小题,每小题 6分,共 18分。
题号 8 9 10
选项 AC AB BCD
三、实验题:共 16分。
11.(8分)
(1) (2分)
(2)A(1分) E(1分)
(3)b(2分) k(2分)
12.(8分)
(1) 正 (2分)
(2) 1399(2分) 1 (2分)
1
(3)变小(2分)
四、计算题:共 38分。
13.(9分)
(1)小球在竖直平面内做匀速圆周运动
= .......................................................................................................................(2分)
= ...........................................................................................................................(1分)
(2)小球受到的洛伦兹力提供向心力
=
................................................................................................................(2分)
= ..........................................................................................................................(1分)
(3) = ................................................................................................................(2分)
= .........................................................................................................................(1分)
14.(13分)
(1)设粒子在 P点速度为 v
= ....................................................................................................................(1分)
粒子由 A到 P做类平抛运动
= ..............................................................................................(2分)
=
..............................................................................................................(2 分)
(2)设 OP长为 x
= ·····················································································(1分)
2
粒子在磁场中做匀速圆周运动,半径为 r,速度为 v
= ····················································································(2分)
= ······················································································(1分)
= ···················································································(1 分)
(3)粒子在第四象限运动时间
=
= .............................................................................................................
(1分)
在第一象限运动时间
= .............................................................................................................(1分)
总时间
= + = + .....................................................................................(1分)
15.(16分)
(1)A与 B发生弹性碰撞,碰后 A、B速度分别为 v1,v2,
由动量守恒定律,以 A的初速度方向为正
= + ..........................................................................................(2分)
由能量守恒定律
= + × ......................................................................(2分)
= ...................................................................................................................(1分)
B从 O点离开后做平抛运动,在 P点
=
=
= = ..............................................................................................................(1分)
(2)粒子在MN区域中做匀速直线运动
3
= .........................................................................................................(1分)
= .....................................................................................................................(1分)
= ..............................................................................................................(1分)
(3)由几何关系
+ = +
= ............................................................................................................................(2分)
在圆弧轨道,等效重力 ‘ = 方向与 ‘ 垂直...............................................(1分)
等效最低点为 ‘, 与 ‘等高,在 ‘处小球对轨道压力最大,设小球速度为 ‘,
小球从 到 ‘ 做圆周运动
= ‘ .................................................................................(2分)
在 ‘位置
‘
′ = ................................................................................................(1分)
小球对轨道的压力
= ′ = + ..........................................................................................(1分)
4