Question

To smell cold food we have to go near

Answer 1

to small cold food we need to go near to small because the rate of diffusion in food is too slow
rather if we cook a heated food we can smell it from far distances.

Answer 2

When molecules of some volatile substances from hot sizzling food diffuse into air and reach the odur sensitive part of our nose we have the perception of smell.

At higher temperature of molecules diffuse into air at a faster rate and therefore travel long distances.

Hence the smell of hot sizzling food reaches as quickly even when we are several metres away.

While on the contrary , when the food is called the vapour diffuse is at a slower rate and therefore does not travel longer distances.

So, one has to come closer to have the perception of smell.