题目
关于波的,不过是英语的~
1.A source of sound waves of frequency 1.0 kHz is traveling through the air at 0.50 times the speed of sound.(a) Find the frequency of the sound received by a stationary observer if the source moves towards her.(b) Repeat if the source moves away from her instead.
(a) 5.0 kHz; (b) 679 Hz
(a) 2.0 kHz; (b) 667 Hz
(a) 7.0 kHz; (b) 677 Hz
(a) 2.0 kHz; (b) 677 Hz
(a) 5.0 kHz; (b) 667 Hz
2.An air bubble ascends from the bottom of a lake 9.2 m deep.The temperature at the bottom of the lake is 8 C,and near the surface it is 25 C.How many times larger in volume is the bubble at the top of the lake compared with its volume at the bottom?
3.You place 3.7 g of water at room temperature in a pressure cooker (a sealed pot) of volume 2.7 L and heat the water to 204 C.What is the pressure in the cooker?
4.The pitch of the sound from a racecar engine drops the musical interval of a fourth when it passes the spectators.This means the frequency of the
1.A source of sound waves of frequency 1.0 kHz is traveling through the air at 0.50 times the speed of sound.(a) Find the frequency of the sound received by a stationary observer if the source moves towards her.(b) Repeat if the source moves away from her instead.
(a) 5.0 kHz; (b) 679 Hz
(a) 2.0 kHz; (b) 667 Hz
(a) 7.0 kHz; (b) 677 Hz
(a) 2.0 kHz; (b) 677 Hz
(a) 5.0 kHz; (b) 667 Hz
2.An air bubble ascends from the bottom of a lake 9.2 m deep.The temperature at the bottom of the lake is 8 C,and near the surface it is 25 C.How many times larger in volume is the bubble at the top of the lake compared with its volume at the bottom?
3.You place 3.7 g of water at room temperature in a pressure cooker (a sealed pot) of volume 2.7 L and heat the water to 204 C.What is the pressure in the cooker?
4.The pitch of the sound from a racecar engine drops the musical interval of a fourth when it passes the spectators.This means the frequency of the
提问时间:2021-01-04
答案
1.设声源相对媒质的运动速度为v观察者相对媒质的速度为u,媒质中的声速为c,声源的振动频率与观察者接收到的频率分别为f0与f,多普勒效应公式的一般表达式为 (1)相对运动 f=(c+u)/(c-v)*fo (2)背离运动 f=(c-u)/...
举一反三
我想写一篇关于奥巴马的演讲的文章,写哪一篇好呢?为什么好
奥巴马演讲不用看稿子.为什么中国领导演讲要看?
想找英语初三上学期的首字母填空练习……
英语翻译
1,人们染上烟瘾,最终因吸烟使自己丧命.
最新试题
热门考点
- 1七律长征中万水千山.等闲 逶迤 细浪 磅礴
- 2单质的化合价是0 那为什么O2是单质它的化合价也是0吗?O的化合价常常是-2 这个是特殊的?还有H202也一样
- 3求二个“看待追星”的作文 一定不能太长100字就行
- 4英语选择题(2道,要原因)
- 5when she heard the terrible news,she was scared.为什么不用heard of?
- 6多少克过氧化氢与98克硫酸所含氧元素的质量相等?
- 7计算 (x-0.5)^2(0.5+x)^2
- 899的平方减98乘100 咋算
- 9甲、乙两人练习跑步,从同一地点出发,甲每分钟跑250米,乙每分钟跑200米,甲比乙晚出发3分钟,结果两人同时到达终点,求两人所跑的路程.
- 10甲、乙两人从A,B两地同时出发,甲骑自行车,乙开汽车,沿同一条路线相向匀速行驶.出发后经3小时两人相遇.已知在相遇时乙比甲多行了90千米,相遇后经1时乙到达A地.问甲、乙行驶的