Convert a density value of 35 kg/m³ to lb/ft³ • Convert the energy of 1.3×10^5 Calorie to BTU • Convert an enthalpy value of 2475 kJ/kg to Btu/lb • A bread has the density around 250+X Kg/m³ convert it to g/cm³. Where, X is the last digit of your ID number.
Convert a density value of 60 lb/ft³ to kg/m³ We know, 2.2 Lb = 1 kg 60 Lb = \frac{60}{2.2} = 27.27 kg and 3.28 ft = 1 m 1ft = \frac{1}{3.28} m = 0.3048 m Then, 60lb/ft³ = \frac{27.27}{(0.3048)³} = 963 kg/m³ Problem to practice • Convert a density value of 35 kg/m³ to lb/ft³ • Convert the energy of 1.3×10^5 Calorie to BTU • Convert an enthalpy value of 2475 kJ/kg to Btu/lb • A bread has the density around 250+X Kg/m³ convert it to g/cm³. Where, X is the last digit of your ID number.
The Correct Answer and Explanation is:
1. Convert 35 kg/m³ to lb/ft³
We use the conversion factor: 1 kg/m³ = 0.06243 lb/ft³ So: 35 × 0.06243 = 2.185 lb/ft³
2. Convert 1.3 × 10⁵ Calories to BTU
We use: 1 Calorie = 0.00396567 BTU So: 1.3 × 10⁵ × 0.00396567 = 515.54 BTU
3. Convert 2475 kJ/kg to BTU/lb
We need: 1 kJ/kg = 0.4299 BTU/lb So: 2475 × 0.4299 = 1063.53 BTU/lb
4. Convert (250 + X) kg/m³ to g/cm³
Let us assume the last digit of your ID number is 4. That gives 254 kg/m³. We know: 1 kg/m³ = 0.001 g/cm³ So: 254 × 0.001 = 0.254 g/cm³
Detailed Explanation
Unit conversion is essential when translating scientific data across different measurement systems. For density, energy, and enthalpy, consistent units are necessary to make accurate comparisons and calculations.
To convert kg/m³ to lb/ft³, you apply the factor that 1 kg/m³ equals approximately 0.06243 lb/ft³. This accounts for both mass and volume in different unit systems. Likewise, to reverse it—converting lb/ft³ to kg/m³—you multiply by approximately 16.0185.
Calories to BTU involve energy conversion across nutritional and thermal contexts. Since 1 Calorie (dietary) is equivalent to about 0.00396567 British Thermal Units (BTUs), multiplying provides the total thermal energy in BTUs. BTUs are commonly used in heating and energy systems, especially in the United States.
Converting enthalpy from kJ/kg to BTU/lb is critical in thermodynamics. Since 1 kJ/kg corresponds to 0.4299 BTU/lb, this enables consistent analysis in systems using imperial units. This is particularly useful in engineering, HVAC, and power plant calculations.
For converting density of a material like bread from kg/m³ to g/cm³, remember that 1000 kg equals one million grams and 1 m³ equals 1,000,000 cm³. That simplifies to the factor 1 kg/m³ = 0.001 g/cm³. This conversion is especially handy when dealing with small-scale lab measurements where gram and centimeter are more practical units than kilogram and meter.
