Question

The density of air is 1.28 g litre^-1 . Express it in : (a) g cm^-3 (b) kg m^-3 .​

Answer 1

Answer:

• a) 0.00128 g/cm³ or 0.00128 g cm⁻³
• b) 1.28 kg/m³ or 1.28 kg m⁻³

Step-by-step explanation:

Given:

• The density of air is 1.28 g litre⁻¹.

To express it in:

• a.) g cm⁻³
• b.) kg m⁻3

Solution:

a.)

First expressing it in g/cm³ or g cm⁻³.

• 1 g/litre = 1/1000 g/cm³
• 1.28 g/litre = 1.28 × 1/1000 g/cm³
• = (1.28/1000) g/cm³

Put decimal point after 3 numbers rest will remain same. ( For adding 3 more numbers we will take zero ( 0 ) in place of that numbers as;

• = 0.00128 g/cm³

[ Also before the point we will take 0 and not just leave the blank character as .00128 g/cm³. Before the decimal point we don't have any number, so we will take zero.]

b.)

First expressing it in kg/cm³ or kg cm⁻³.

• 1 g/cm³ = 1/1000 kg/cm³
• (1.28/1000) g/cm³
• = (1.28/1000) × 1/1000 kg/cm³

Here, 1000 in both numerator and denominator gets cancel, we have:

• = 1.28 kg/cm³

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