Question

A god characteristics of fuel is that it:
A. Leaves more ash
B. Leaves no ash
C. Is highly expensive
D. None of the above

Answer 1

Hint: Imagine driving in any vehicle, you do not want the fuel burning in the engine to produce a lot of smoke residue in the process. Our travel expenses will increase if the fuel is expensive. So this also decides whether a fuel is good or not.

Complete step by step solution:
All the machines, regardless of how complex they are built and how complex tasks they complete require fuel for their smooth operation. Now these fuels, in the first place should produce maximum energy with the least amount of volume consumed. This is measured by calorific value. The burning should not be explosive, which means the combustion process should be easy to control. It is difficult to manage the machines if the fuel leaves a lot of residue in the form of ash or any other carbon deposits after the combustion process.
Machines are also used to increase productivity and decrease the per unit charges of utility for example mileage of a car. Now, the mileage also depends on the type and condition of the engine of the car. But the charges per unit volume of the fuel you put in your vehicles also decide the charges you will have to bear. Thus, out of the given choices, we can say option B is the correct one.
The other characteristics are that they should have less moisture content and should be easy to handle and transport. The ignition temperature should not be very high or very low. This also decides whether the fuel combustion is easy to start or stop.

Note: There is no one common fuel of all the machines that we depend on. Every machine has a list of fuel options. For most of the time we have to decide the best fuel from the available choices. The above factors help us decide the same. But there is always scope to better the quality of existing fuels or engines, machines we depend on.