Maybe he points his little light detector at it and it reads out.

他可能会用一个光检测器对准苹果,仪器显示计量结果

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And for those particles that make it past the caesium iodide, a huge electromagnet tracks their passage out of the detector.

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He came across the ring while out with his metal detector in February 2004.

BBC: Gold 16th century ring

If I get delayed at the metal detector, the laptop won't be sitting out in the open for a long time.

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