Question

which way does the smoke flow when the incense stick is kept near the edge of the mouth of beaker

Answer 1

Due to the process of diffusion the gas particles from the incense stick will move in the all possible directions, hence the smoke will flow in all the possible directions

Answer 2

Answer:

• When the "incense stick" is kept near the 'edge of the mouth' of the beaker, the smoke will flow towards the candle kept inside the beaker and then above.
• This is because the air at the edge of the beaker is cooler than the air inside the beaker.
• The smoke from the burning candle creates a low-pressure zone above it in the beaker and hence the smoke from the incense stick goes there to fill the low-pressure zone.
• The movement of smoke is not a straight pathway but circulates or spirals from an area of 'high-pressure zone' to an area of low-pressure zone.
• This is an example of how low and high air pressures are formed in the atmosphere.