(10·安徽 B 篇)Have you ever wondered
Why do airplanes take longer to fly west than east
It can take five hours to go west-east from New York(NY) to London bur seven hours to travel east-west from London to NY
The reason for the difference is an atmospheric phenomenon known as the jet(喷射) stream
The jet stream is a very high altitude wind which always blows from the west to the east across the Atlantic
The planes moving at a constant air speed thus go faster in the west-east direction when they are moving with the wind than in the opposite direction
What would happen if the gravity on Earth was suddenly turned off
Supposing we could magically turn off gravity
Would buildings and other structures(建筑物) float away
What happened would depend on how strongly the things were attached to t