một vật có khối lượng 8100g. Thể tích của vật là 3dm3. Khối lượng riêng của vật là?

2 câu trả lời

$m= 8100g= 8,1kg$ 

$V= 3 dm^3= 0,003 m^3$  

$\Rightarrow D= \frac{m}{V}= \frac{8,1}{0,003}= 2700 kg/m^3$

Đổi 8100g = 8,1kg; 3dm3 = 0,003m3
Khối lượng riêng của vật: D = m / V = 8,1 / 1,003 = 2700 (kg/m3)

 

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