单词：maximum sound pressure
单词：maximum sound pressure 相关文章
STEVE EMBER: Im Steve Ember. SHIRLEY GRIFFITH: And Im Shirley Griffith with EXPLORATIONS in VOA Special English. Today we travel to India by way of the John F. Kennedy Center for the Performing Arts in Washington, D.C. This cultural organization is c
2011年VOA慢速英语(三)月
The air thins and they begin to lose the protective weight of the miles of air above them. The pressure is dropping, when you finally get to the stratosphere, and to the altitude we like to work at, it's only one one hundredth that of it's on the gro
探索与发现2014年
On airplanes, cabin pressure changes during takeoff and landing to help passengers breathe easy at high altitudes. These changes in air pressure may make adults ears feel a little funny, prompting a few yawns to equalize the pressure. But for babies,
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DAVID GREENE, HOST: Both President Trump and Vice President Mike Pence will go to Dallas on Friday for the NRA's annual convention. On one hand, the president's presence shows that the NRA has staying power. But the organization has also faced fresh
2018年NPR美国国家公共电台5月
Snowflakes are small ice crystals. Snowflakes near the ir melting temperature can, through hand pressure, be made to fuse into a snowball by a process of melting and re-freezing. The snow yields to pressure gently and progressively and doesnt make so
英语时差8，16