A family requires 20,000 KJ of fuel energy every day. If calorific vlaue of the fuel used by them is 15,000 kJ/kg, how much of this fuel will be

required by this family to meet their energy needs for the month of April?

40 kilograms of fuel are required to meet their energy needs for the month of April.

Explanation:

The month of April has 30 days and the full energy needed by the family is determine by the following combustion formula, derived from dimension analysis:

(1)

Where:

- Mass of the fuel, measured in kilograms.

- Calorific value of the fuel, measured in kilojoules per kilogram.

- Daily fuel energy, measured in kilojoules.

- Number of days of the month, dimensionless.

If we know that , and , then the amount of fuel required to meet their energy needs for the month of April is:

40 kilograms of fuel are required to meet their energy needs for the month of April.

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