A child is drinking a liquid with a straw. Which of the following statements is true?
A) The fluid is being pulled up into the straw.
B) Longer straws work better because the pressure is larger deeper down.
C) The pressure inside the straw depends on the viscosity of the liquid.
D) The pressure in the straw is reduced and the liquid is pushed upward by atmospheric pressure on the surface of the liquid.

Question

Quizplus · Accepted Answer

When a child drinks liquid through a straw, the pressure is reduced inside the straw by sucking air out of it. This reduction in pressure causes atmospheric pressure on the surface of the liquid to push it up the straw and into the child's mouth. This phenomenon is known as suction.

Option A is incorrect because the fluid is not being pulled up into the straw, but rather pushed up by atmospheric pressure.

Option B is incorrect because the pressure inside the straw decreases as the length of the straw increases.

Option C is incorrect because the pressure inside the straw is not affected by the viscosity of the liquid.

A Child Is Drinking a Liquid with a Straw