文档内容
2025 年高考模拟考试
物理试题参考答案及评分标准
题号 1 2 3 4 5 6 7 8 9 10 11 12
答案 B C B B A C A D AD BC BD ACD
13.(6分)(1)C (2)9.150 (3)750 (每空2分)
14.(8分)(1)b (3)R R (每空2分)
G 1
15.(8分)解析:(1) 气泡在池底时压强 p p gh1.5105Pa …………………(1分)
1 0
pV pV
由理想气体状态方程得 1 1 0 2 ···········································(2分)
t 273 t 273
1 0
解得
t
17oC················································································(1分)
1
p p
(2) 气泡上升过程中,外界对气体做功为W 0 1(V V)···············(2分)
2 2 1
由热力学第一定律U W Q·························································(1分)
解得Q=0.39J················································································ (1分)
16.(8分) 解析:
(1) 金属棒恰好静止,有mgsinILB 1分
E
I ························································································(1分)
2R
E nk ························································································(1分)
2mgRsin
解得磁通量的变化率k ···················································(1分)
nLB
B2L2v
(2) 速度最大时,有mgsin m ··············································· (1分)
2R
金属棒加速运动过程中,有mgsintILBt mv 0························(1分)
m
E BLv
I ···············································································(1分)
2R 2R
vtx
2mR B2L2x
解得t ································································(1分)
B2L2 2mgRsin
高三物理答案 第1页(共3页)17.(14分) 解析:
v2
(1) 根据洛伦兹力提供向心力qvBm 1 ……………………………………(2分)
1 r
1
由题意可知最小半径为r L··························································· (1分)
1
qBL
解得v ··············································································· (1分)
1 m
5qBL
(2)由题意可知最大速度v
2 3m
5
最大半径r L···········································································(1分)
2 3
r
设v 与y轴夹角为,则sin 1 ···················································(1分)
2 r
2
在O点,粒子的最大速度在y轴方向上的分速度v =v cos·················(1分)
y 2
v2
粒子穿过小孔后在平行于yOz平面上做匀速圆周运动,由qv Bm y 得
y R
粒子做匀速圆周运动的最大半径 ············································(1分)
8
穿过小孔的粒子到达接收屏前离开x轴的最大距离d 2R L············· (1分)
1 3
(3)设在P点发射的速度为v介于v 与v 间的粒子与y轴的夹角为θ,则
1 2
L mv
粒子在磁场中的运动半径r ·············································(1分)
sin qB
qBL
粒子穿过小孔后沿x轴方向的分速度v =vsin ··························(1分)
x m
2m
粒子做圆周运动的周期T ·······················································(1分)
qB
当粒子运动时间为整数个周期时,这些粒子打在接收屏上同一点。
1 qE
d v nT (nT)2··································································(1分)
2 x 2 m
解得 (n=1,2,3,…)··········································(1分)
,
高三物理答案 第2页(共3页)18.(16分)解析:
(1)由图乙可知, 时,A与C恰好一起运动。
m 1kg
1
对C由牛顿第二定律可得m g m a ···············································(2分)
2 2 1
解得a 2m/s2············································································(1分)
1
(2)B的质量 m 1kg时,
1
对A、B、C由牛顿第二定律可得m g m m Ma ························(1分)
1 1 2 1
B的质量 m 2kg 时,由图乙可知A的加速度 a 4m/s2·····················(1分)
1 2
对A、B由牛顿第二定律可得mgm g mMa ························· (1分)
1 2 1 2
联立解得M 2kg,
m
2kg···························································(2分)
2
(3)当m 2kg时,设B运动时间t后落地。
1
则此时C的速度v at2t····························································(1分)
C 1
A的速度v a t4t·····································································(1分)
A 2
从B落地到C恰好到达Q点的过程中,A与C组成的系统在水平方向上动量守恒,可
得m v Mv m Mv·····························································(1分)
2 C A 2
解得 v3t
1 1
t时间内,A与C的相对位移Δx a t2 at2···································(1分)
2 2 2 1
解得 Δxt2
从B落地后到C恰好到达Q点的过程中,由能量守恒得
1 1 1
m v2 Mv2 m gLΔxm gr m Mv2···························(2分)
2 2 C 2 A 2 2 2 2
1
B下落的高度 h a t2···································································(1分)
2 2
解得h=4m····················································································(1分)
高三物理答案 第3页(共3页)