1.Nối hai quả cầu A và B bằng dây dẫn người ta thấy êlêctron dịch chuyển trong dây dẫn theo chiều từ A đến B. Kết luận nào sau đây là đúng khi nói về điện tích của hai quả cầu A và B? A nhiễm điện âm, B nhiễm điện dương A không nhiễm điện, B nhiễm điện âm. A nhiễm điện dương, B không nhiễm điện A nhiễm điện dương, B nhiễm điện âm. 2.Trường hợp nào sau đây, đổi đơn vị đúng? 220V = 0,022KV 1200V = 1,2KV 50KV = 500000V 4,5V = 450mV 3.Trong đoạn mạch 2 bóng đèn mắc nối tiếp có cường độ dòng điện qua bóng đèn 1 là I1= 1A, Hỏi cường độ dòng điện qua đèn 2 bằng bao nhiêu? I = 0,5A I = 1A I = 1,5A I = 2A 4.Để đo được dòng điện trong khoảng 0,10A - 2,20A ta nên sử dụng ampe kế có ĐCNN và GHĐ như nào? 0,2A-2A 0,01 A-3A 0,1 A-2A 0,3A-3A

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