Energy correlation between Pizza and Diesel

Assume a slice of pizza weighing 100 g has 250 Calories. Correlate its energy content to diesel (calorific value of diesel is 44000 kJ/kg; density of diesel is 0.83 kg L^–1).

 

One dietary Calorie, C is equal to 1 kilocalories (kcal).  

1 calorie = 4.184 Joules.

1 kg or 1000 g diesel has 44000 kJ = 44000/4.184 ≈ 10516 kcal.

 

In other words, 10516 kcal are present in 1000 g of diesel.

 

It is mentioned that, 100 g pizza = 250 kcal (or 250 C).

Therefore, 250 kcal are present in (250×1000)/ 10516 = 23.8 g diesel.

 

Density of diesel = 0.83 kg L^–1 = 830 g per 1000 mL.

 

This means, 830 g diesel occupies 1000 mL volume.

  

∴ 23.8 g diesel = (23.8×1000)/830 ≈ 28.7 mL.

 

Hence, 100 g pizza with 250 Calories ≅ 28.7 mL of diesel.