Airplanes have shadows. Watch as an airplane flies over your head. You may see its shadow on the ground. 飞机有阴影。看着一架飞机飞过你的头顶。你可能会在地面上看到它的影子。 A cloud has a shadow. Sometimes the s...
“Are you in a bad mood (情绪)?” Tex asked. “Tex, just leave me alone!” I got up, making my way towards the living room. “What’s up, David?” asked my father. “I’m in a terrible mood!” I said. “I like organizing things when I’m in a bad mood,” said my dad...
; if they are, that makes the process faster, but it still works even if they aren't. Queuing works in a similar way, but a bit more behind the scenes. Normally a program assembles the message on your behalf, based on some activity of yours, such as entering an order. The program...
These are contrails emitted from airplanes. Contrails, or condensation trails, are essentially human-made clouds; they are trails of condensed water vapor created by jet engines, according to the National Weather Service. We most commonly see them behind planes at cruising altitude, but they ...
Cloud seeding exists in theory and in practice. But does it really work? Studies are mixed on the effectiveness of cloud seeding in different environments. One problem is that it’s difficult to determine whether clouds are going ...
Airplanes are a means of ignoring the spaces in between your point of origin and your destination. By contrast, a surface journey allows you to look out on those spaces—at eye level and on a human scale, not peering down through breaks in the clouds from 35,000 feet above—from the ...
Sensors the size of a Coke can are dropped from Air Force airplanes to take data from the gaps inside an atmospheric river that satellites don’t see. These sensors gather temperature, pressure, wind, and moisture information that feeds into world weather prediction models. To predict precipitatio...
2. What are the advantages of electric cars according to the passage?a. Using cheap oil. b. Making little noise.c. Running at low costs. d. Producing no air pollution. A.a and b B.c and d C.b and c D.a and d3. The last sentence of the passage is written to ___. A.show...
As the fan blades turn, they force air forward, toward the exhaust port (check out How Airplanes Work to find out what causes this). When air particles are driven forward, the density of particles (and therefore the air pressure) increases in front of the fan and decreases behind the fan...
If you’ve looked up in the sky and seen the trail of lights that kind of looks like the trail Santa’s sleigh might leave behind as he travels from house to house around the world, what you’re seeing is actually theStarlink satellites. ...