初中物理知识点总结(最新最全)
购物车的英文Summary of r High School Physics Knowledge (XXX)
Chapter 1: Sound XXX
think of1.Sound n: It is produced by the n of an object。When the n s。the XXX.
curiosity2.Sound n: Sound is transmitted through a medium。It cannot travel through a vacuum。Usually。the sound we hear is XXX.
3.Speed of sound: The speed of sound in air is 340 meters per cond。Sound travels XXX。and XXX.
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4.Measuring distance using echo: S=1/2vt
5.Three characteristics of musical sound: pitch。loudness。and timbre。(1) Pitch refers to the highness or lowness of a sound。which is related to the frequency of the sound source。(2) Loudness refers to the volume of a sound。which is related to the amplitude of 怎么学俄语
the sound source and the distance een the source and the listener.
6.Ways to ce noi: (1) ce it at the source。(2) ce it during n。(3) ce it XXX.
英语标点符号the shawshank redemption7.Audible sound: XXX 20Hz and 20,000Hz。Ultrasonic waves: XXX 20,000Hz。Infrasonic waves: XXX 20Hz.
8.Characteristics of ultrasonic waves: Good nality。strong XXX。XXX。ultrasound。XXX。ultrasonic cleaners。and XXX welders.
9.Characteristics of infrasonic waves: They XXX distances。easily bypass obstacles。and XXX。tsunamis。earthquakes。etc。In n。XXX launches。airplane flights。train and car travel。and nuclear ns XXX.
弋果美语Chapter 2: XXX
1.XXX: It XXX of an object。The tool ud to measure it is a thermometer。which is bad on the XXX liquids.
findchips
to me2.Celsius temperature (℃): The unit is degrees Celsius。One degree Celsius is defined as the temperature of a mixture of ice and water。and 100 degrees is defined as the temperature of boiling water at standard atmospheric pressure。The range een 0 and 100 degrees is divided into 100 equal parts。with each part equal to 1℃.
