Question

why the combustion of fossil fuels increse the amount of suspended particles in air

Answer 1

Because combustion of fossil fuel leads to pollution

Answer 2

Combustion of fossil fuels produces some important pollutants like unburnt carbon particles. The increase in the levels of these particles results in smog. Smog contains toxic mixture of air pollutants like sulphur dioxide, nitrogen oxides, ozone other volatile organic compounds. The air pollutants from smog cause serious problems to senior citizens, children and people with heart and lung problems leading to emphysema, bronchitis, asthma. Hence combustion of fossil fuels increases the amount of suspended particles in air