Air pressure is 1.0 * 10⁵N/m², air density is 1.3 kg/m³, and the density of soft drinks is 1.0 * 10³ kg/m³. If one blows carefully across the top of a straw sticking up 0.080 m from the liquid in a soft drink can, it is possible to make the soft drink rise half way up the straw and stay there. How fast must the air be blown across the top of the straw?

Question

Quizplus · Accepted Answer

The speed of the air must be such that the pressure drop due to the airflow equals the pressure difference needed to lift the liquid halfway up the straw. Using Bernoulli's equation and the given densities, the required speed is calculated to be approximately 25 m/s.

Air Pressure Is 1