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Question 1 · Single choice · 中档
在冰上接力比赛时,甲推乙的作用力是 $F _ { 1 }$ ,乙对甲的作用力是 2,则这两个力( ) $F _ { 2 }$
A. 大小相等,方向相反 B. 大小相等,方向相同 C. $F _ { 1 }$ 的冲量大于 $F _ { 2 }$ 的冲量 D. $F _ { 1 }$ 的冲量小于 $F _ { 2 }$ 的冲量
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Question 2 · Single choice · 中档
A. $_ { 9 2 } ^ { 2 3 8 } \mathrm { U } _ { 9 0 } ^ { 2 3 4 } \mathrm { T h } + _ { 2 } ^ { 4 } \mathrm { H e }$ B. $\mathbf { \Sigma } _ { 7 } ^ { 1 4 } \mathbf { N } + \mathbf { \Sigma } _ { 2 } ^ { 4 } \mathbf { H } \mathbf { e } \to \mathbf { \Sigma } _ { 8 } ^ { 1 7 } \mathbf { O } + \mathbf { \Sigma } _ { 1 } ^ { 1 } \mathbf { H }$ C. $_ { 9 0 } ^ { 2 3 4 } \mathrm { T h } \to _ { 9 1 } ^ { 2 3 4 } \mathrm { P a } + _ { - 1 } ^ { 0 }$ e D. $_ { 9 2 } ^ { 2 3 5 } \mathrm { U } + _ { 0 } ^ { 1 } \mathrm { n } _ { 5 6 } ^ { 1 4 4 } \mathrm { B a } + _ { 3 6 } ^ { 8 9 } \mathrm { K r } + 3 _ { 0 } ^ { 1 } \mathrm { n }$
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Question 3 · Single choice · 中档
如图为一用透明材料做成的中心是空的球,其中空心部分半径与球的半径之比为1:3。当细光束以 $3 0 ^ { \circ }$ 的入射角射入球中,其折射光线刚好与内壁相切,则该透明材料的折射率为( )
A. $\sqrt { 2 }$ B. 1.5 C. $\sqrt { 3 }$ D. 2
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Question 4 · Single choice · 中档
在同一地方,甲、乙两个单摆做振幅不同的简谐运动,其振动图像如图所示,可知甲、乙两个单摆的摆长之比为( )
A. 2:3 B. 3:2 C. 4:9 D. 9:4
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Question 7 · Single choice · 中档
我国的石桥世界闻名,如图,某桥由六块形状完全相同的石块组成,其中石块1、6固定,2、5质量相同为 m,3、4 质量相同为 $m ^ { \prime }$ ,不计石块间的摩擦,则 $m : m ^ { \prime }$ 为( )
A. $\frac { \sqrt { 3 } } { 2 }$ B. $\sqrt { 3 }$ C. 1 D. 2
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Question 9 · Multiple choice · 中档
火星与地球的质量比为a,半径比为b,则它们的第一宇宙速度之比和表面的重力加速度之比分别是(
A. $\frac { g _ { \mathcal { L } } } { g _ { \# \emptyset } } = \frac { a } { b }$ B. $\frac { \nu _ { . \chi } } { \nu _ { _ { \mathrm { H } } } } = \sqrt { \frac { a } { b } }$ C. $\frac { g _ { \mathcal { k } } } { g _ { \mathtt { H h } } } = \frac { a } { b ^ { 2 } }$ D. $\frac { \nu _ { { } , k } } { \nu _ { { \scriptscriptstyle \mathrm { f i f } } } } = \sqrt { \frac { b } { a } }$
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Question 10 · Multiple choice · 中档
一群处于 $n = 4$ 激发态的氢原子跃迁向外辐射出不同频率的光子,则( )
A. 需要向外吸收能量 B. 共能放出6种不同频率的光子 C. $n = 4$ 向 $n = 3$ 跃迁发出的光子频率最大 D. $n = 4$ 向n =1跃迁发出的光子频率最大
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Question 15 · Free response · 中档
足够长的玻璃管水平放置,用长19cm的水银封闭一段长为25cm的空气柱,大气压强为76cmHg,环境温度为300K,将玻璃管缓慢顺时针旋转到竖直,则:
①空气柱是吸热还是放热
②空气柱长度变为多少
③当气体温度变为360K时,空气柱长度又是多少?
Answer key (1) 放热; (2) 20cm; (3) 24cm
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Question 16 · Free response · 中档
有一个角度可变的轨道,当倾角为30<sup>o</sup>时,A恰好匀速下滑,现将倾角调为 $6 0 ^ { \circ }$ ,从高为h的地方从静
止下滑,过一段时间无碰撞地进入光滑水平面,与B发生弹性正碰,B被一根绳子悬挂,与水平面接触但不挤压,碰后B恰好能做完整的圆周运动,已知A的质量是B质量的3倍,求:
①A与轨道间的动摩擦因数;
②A与B刚碰完B的速度大小;
③绳子的长度 L。
Answer key (1) $\mu = \frac { \sqrt { 3 } } { 3 }$; (2) $\sqrt { 3 g h }$; (3) 0.6h
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