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thanhluc2002
2 năm trước
Một electron có vận tốc ban đầu không đáng kể được tăng tốc bỡi hiệu điện thế U = 106V. Sau khi được tăng tốc, nó được cho bay vào từ trường đều với - a) Vận tốc của electron khi nó bắt đầu bay vào từ trường là bao nhiêu? - b) Tìm lực Lo-ren-xơ tác dụng lên electron? Biết B = 2.10-4T. - c) Tìm bán kính quỹ đạo và chu kì quay của electron.
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