Question 5: Why does smoke rise faster in a chimney on a windy day?
Answer
On a windy day the smoke rise faster in the chimney. The phenomena can be explained on the basis of Bernoulli’s equation.
Bernoulli’s Principle is
P = pressure of the fluid
ρ = density of the fluid
v = velocity of the fluid.
So, when velocity of the fluid is increased, the pressure must decrease in order to keep the sum of the equation on LHS constant.
Now when wind is blowing, the velocity of the air is increased over the top of the chimney. However, the pressure below (chimney, kitchen etc) is larger. The difference in pressure on the top of the chimney and beneath, forces the air and smoke particles inside the chimney to rush upward toward the low pressure at the top of the chimney. Therefore, the smoke rises faster when wind (air) is blowing.
Follow up question
Why does the smoke rises up in the chimney at all?
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