If air weren't admitted into the bell jar the electric bell in the bell jar would not ring because of a lack of a medium.
如果我们不让空气进入铃罩,铃罩中的电铃一定会因缺少介质而不响了。
If air weren't admitted into the bell jar, the electric bell in the bell jar would not ring because of a lack of a medium.
如果我们不让空气进入铃罩,铃罩中的电铃一定会因缺少介质而不响了。
A toughness cushion ring is arranged at the bottom of the threaded column on the jar lid.
在坛盖上螺纹拄的底部,有一韧性垫圈。
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