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pepopoma2
2 năm trước
Một xilanh đang chứa một khối khí ở áp suất khí quyển 1atm. Hỏi phải đẩy pit- tông theo chiều nào, một đoạn bằng bao nhiêu để áp suất khí trong xilanh tăng gấp 3 lần? Coi nhiệt độ của khí không đổi trong quá trình trên. Tính lực cần giữ pit tông khí đó, biết diện tích pit tông là 20 cm khối
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