Q15 of 17 Page 236

When we “suck” using a straw, the liquid travels up into it. Explain why?

When we suck a straw just dipped in water the air inside is removed which creates a region of low pressure. As the atmospheric pressure acting on the surface of the water is also acting on the submerged tip of the straw (by Pascal’s Law), the water flows upward along the straw.


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