Question

A milkshake has a viscosity of 0.60Pa⋅s. To drink this shake through a straw of diameter 0.56cm and length 22cm, you need to reduce the pressure at the top of the straw to less than atmospheric pressure.

Answer 1

When you suck the air out of a straw, it creates a low pressure zone inside, allowing the atmospheric pressure to push the liquid up the straw and into your mouth.

Step-by-step explanation:

In order to drink a milkshake through a straw, you need to reduce the pressure at the top of the straw to less than atmospheric pressure. When you suck the air out of the straw, it creates a low pressure zone inside of it. With a low-pressure zone, there is nothing pushing down on the liquid, so it moves upward easily. This decrease in pressure inside the straw allows the higher atmospheric pressure on the outside to push the milkshake up the straw and into your mouth.