Demonstrate the formation of convective currents.
Convection currents are set up in the air. To demonstrate their formation, let us consider the following experiment:
Place a candle in a beaker and light it. Now, light an incense stick and bring it to the edge of the mouth of the beaker. Observe the direction of flow of smoke. Now, in a similar way, observe the direction of flow of smoke by placing the stick a little above the candle and then at other regions above the beaker.
You will observe that the direction of flow of smoke is different in all the situations. The patterns of flow of smoke reveal the directions in which hot and cold air move.