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太原市 2023 年高三年级模拟考试(一)
物理参考答案及评分建议
二、选择题:本题共8小题,每小题6分,共48分。在每小题给出的四个选项中,第14~
18题只有一项符合题目要求,第19~21题有多项符合题目要求。全部选对的得6分,选对
但不全的得3分,有选错的得0分。
题号 14 15 16 17 18 19 20 21
选项 C C D B D BD BD BD
三、非选择题:共62分。
22.(6分)
(1) AB
(2)
1
评分 标准:4每 空各2分。
23.(12分)
(1)正 1.1
(2)○
1
○
2 0.96
○
3 2.9 4.8
评分标准:每空(或每图)各2分。24.(10分)
(1)设“冰壶”被推出时瞬间速度的大小为v,继续滑行时加速度
的大小为 ,位移大小 =40m,时间t=10s,由运动学规律有
= t ·· ·· 1 ······················ ·· 1 ··························································(1分)
1 2
0=v- t························································································(1分)
解得 :1 =0.8m/ ,v=8m/s
2
设“冰壶 ” 1与冰面 的动摩擦因数为μ,由牛顿运动定律有
μmg=m ······························································(1分)
解得:μ = 1 0.08 ························································(1分)
运动员推“冰壶”的过程中位移大小 =5m,加速度的大小为 ,
水平恒力的大小为F, 2 2
=2 ······························································(1分)
F 2 -μm g 2 = m 2 ···························································(1分)
解得:F= 1 2 44N ·······················································(1分)
(2)当“冰壶”与冰面的动摩擦因数为μ´=0.1时,设“冰壶”被水平
恒力推出时瞬间速度的大小为v´
,
+ = t
解 1 得 : 2 v´=29m/s ·······················································(1分)
“冰壶”被推出后滑行的加速度为 ´,“冰壶”被水平恒力推出后滑
行的距离为 ´ 1
μ´mg=m ´ 1
=2 ´ 1 ´
‘2
解得: 1 ´1=40.5m ····················································(1分)
水平恒力 1的大小变为F´,其作用距离为 ´,加速度的大小为 ´
+ = ´+ ´ 2 2
解1得 :2 1 ´=4 . 2 5m
=2 ´ 2
‘2
F´-μ´m 2g= m2´´ ´
解得:F´=2 00 2 N ······················································(1分)
另:用动能定理或动量定理求解,方法更优。25.(14分)
v sin30°
(1)粒子在电场中运动时间t =2 0 ····················(1分)
1
a
qE
a= ································································(2分)
m
mv 2
粒子在磁场中运动半径为R, qv B 0 ···················(1分)
0
R
αR
粒子在磁场中运动时间t = ································(1分)
2
v
0
π
由几何关系可知α= ··············································(1分)
3
粒子从a点运动到b点所用的时间t=t +t (1分)
1 2 ··························
mv πm
联立 可得t= 0+ ··········································(1分)
qE 3qB
(2)Ob两点间距离l =2Rsin30° ·······························(1分)
1
粒子第二次在a点速度方向与x轴正方向夹角为θ
v sinθ
v cos30°t =2v cosθ 0 ···········································(2分)
0 1 0
a
Oc两点间距离l =2Rsinθ ························································(1分)
2
bc两点间距离l=l -l (1分)
1 2 ········································································
mv
联立 得l=( 3-1) 0 ················································(1分)
qB
26.(20分)
(1)Q下落:设在最低点速度为 ,
·················· ·· 0 ·····························(1分)
1 2
1 ∙ 0 =2 1 0
在最低点 , ····································(1分)
2
0
解得 − 1 = 1 0 ···································(1分)
(2) Q 0 =和4Pm相/s碰: 设 =碰1后8NQ、P速度分别为 、 ,以左为正
···························· ·· 1 ···· ·· 2 ········ (1分)
1 0 = 1 1+ 2 2 ······················································(1分)
1 2 1 2 1 2
2解 得 1 0 =2 1 1+2 2 2 ································(2分)
碰后: 1 P=在−滑1m板/s上滑动 2,=P3与m滑/s板共速时,相对AB的高度最大,
设此高度为H,比较H与R即可判断能否从C点飞出。
设此时P和滑板的速度大小均为
3······························································(1分)
2 2 = 2+ 3 3 ·····················(1分)
1 2 1 2
2解 得 2 2 =2× 2 ; + 3 3+ 2 + 2
R 3故=不1能m飞/s出···· ···=···0·.·0··5·m······································(2分)
H设<小球碰撞后能摆到的最高点与 的连线和竖直方向的夹角为θ,
′
由机械能守恒定律得
1
mv2 mgL (1cos) ··········································(1分)
2 1 1 1 0
解得 =0.9375, <
0
可知cθo>s ,故碰后小co球s Qc的os运5动不能视为简谐运动········(2分)
0
(3)计5算P两次经过B时的速度,以左为正
···························································(1分)
′ ′
2 2 = 2 2+ 3 3
································(1分)
1 2 1 ′ 2 1 ′ 2
2 2 2 =2 2 2+2× 3 3+ 2
解得 ·················································(1分)
′ 3± 6
2 = 3 m/s
第一次经过B点速度
′ 3+ 6
2+ = 3 m/s
第二次经过B点速度
′ 3− 6
故物体P相对滑板滑动 2 时 − ,= 3 m/s>0
没有相对地面向右运动的速度····································(1分)
在AB段相对滑板从 时间
′
2− 2+ 6− 6
→ 1 = = 15 s
在AB段相对滑板从 相对静止的时间
′
3− 2− 6
物体P相对滑板的水 平→部分 2 = = 15s
AB运动的总时间 ····························(2分)
= 1+ 2 =0.4s