Question

LPG has a lower energy density than either petrol or fuel-oil, so, the equivalent --- is higher.
A. Fuel consumption
B. Fuel-absorption
C. Fuel density
D. Fuel capacity

Answer 1

The energy stored per unit space or volume is known as energy density. Lower energy density means a low amount of energy is stored per unit volume. Higher energy density means a high amount of energy is stored per unit volume.

Complete answer:
- Fuel consumption is the amount of fuel required to produce a known amount of energy.
- It is given that LPG has a lower energy density than either petrol or fuel-oil. It means a low amount of energy is stored per unit of volume of LPG gas whereas a high amount of energy is stored per unit volume of either petrol or fuel-oil. So, if we burn the same amount of LPG and either petrol or fuel-oil, we will get less energy from LPG than either petrol or fuel-oil.
- If we want the same energy from LPG and either petrol or fuel-oil, then we have to burn more equivalent amounts of LPG than either petrol or fuel-oil. So, the consumption of LPG will be high.
- So, LPG has a lower energy density than either petrol or fuel-oil, so, the equivalent fuel consumption is higher.

**Therefore, option (A) fuel consumption is correct.

Note:**
If fuel has low energy density then more fuel will be consumed for more energy production. If fuel has a high energy density then a low amount of fuel will be consumed for the production of a high amount of energy. The mass of fuel present per unit volume is known as fuel density. Fuel is liquid, so it is stored in a tank. The amount of fuel that can be transferred from the fuel tank is known as fuel capacity. The non-transferable amount of fuel remains at the base of the fuel tank.