Question

Mars has an average atmospheric pressure of 0.007 atm. Would it be easier or harder to drink from a straw on Mars than on Earth? Explain. [Section 10.2]

Short answer

It would be easier to drink from a straw on Mars than on Earth. This is because Mars has a significantly lower atmospheric pressure (0.007 atm) compared to Earth (1 atm). The greater pressure difference between the inside and outside of the straw on Mars allows the liquid to be pushed up the straw more easily.

Step-by-step solution

Recall the mechanism of drinking from a straw

When we drink from a straw, we create a partial vacuum inside the straw by sucking out the air, which reduces the pressure inside the straw. The atmospheric pressure outside then pushes the liquid up the straw and into our mouth. The greater the difference between the pressures inside and outside the straw, the more the liquid is pushed up the straw.

Compare the atmospheric pressure on Mars and Earth

We are given that Mars has an average atmospheric pressure of 0.007 atm. The atmospheric pressure on Earth is 1 atm, which is significantly higher.

Analyze the effect of pressure on drinking from a straw

If the pressure difference between the inside and outside of the straw is greater, the liquid will rise more easily in the straw. Since the atmospheric pressure on Mars is significantly lower than that on Earth, the pressure difference between the inside and outside of the straw on Mars would be greater than on Earth.

Determine if it is easier or harder to drink from a straw on Mars

As we concluded in step 3, the pressure difference on Mars is greater than on Earth, which would make it easier for the liquid to be pushed up the straw. Therefore, it would be easier to drink from a straw on Mars than on Earth.

Key concepts

Drinking Mechanism

When we drink from a straw, a fascinating process takes place. Initially, our mouth creates a vacuum by sucking the air out. This action reduces the pressure inside the straw compared to the pressure outside in the atmosphere.
You can think of it like creating a tiny void that's eager to be filled. The air pressure outside is stronger because we've made it weaker inside the straw. This external pressure forcefully pushes the liquid upwards, aiming to balance the pressures.
This is how the liquid travels up the straw and into our mouth without us having to do much. By reducing the pressure in the straw, the atmospheric pressure does all the heavy lifting, almost magically raising the liquid for us to sip.

• We create a vacuum by sucking air out.
• Pressure inside the straw reduces.
• Atmospheric pressure pushes liquid up into the mouth.

Pressure Difference

The concept of pressure difference plays a critical role in many everyday activities, including drinking from a straw. The difference between the atmospheric pressure outside and the pressure we create inside the straw dictates how easily a liquid can rise.
The more significant this difference, the easier it is for the liquid to climb up.
On Earth, with its atmospheric pressure of 1 atm, we traditionally have to create a notable pressure difference to successfully sip our drink. Conversely, when atmospheric pressure is lower, such as on Mars, the pressure difference becomes more pronounced and assists more in lifting the liquid.
To sum up, the larger the outside pressure compared to the inside pressure of the straw, the easier the flow of liquid becomes.

• Pressure difference is key to how fluids rise.
• Bigger differences make it easier for liquids to move.
• Mars's low pressure leads to a larger pressure difference.

Mars Atmosphere

Mars offers a whole different atmospheric scenario compared to Earth. Its atmospheric pressure, measuring about 0.007 atm, is substantially lower than Earth's which is at 1 atm.
This thinner Martian atmosphere means there's less force pushing down on you generally and particularly when you're trying to sip from a straw.
In contrast, this lack of atmospheric pressure increases the pressure difference when you're creating a vacuum inside the straw. As a result, the same amount of effort results in a greater ease to drink on Mars than on Earth.
The unique environment may affect other activities but in terms of sipping through a straw, it surprisingly provides an easier experience.

• Mars has a very low atmospheric pressure of 0.007 atm.
• The reduced pressure increases the pressure difference for easier drinking.
• Mars's atmosphere, although generally weaker, aids in straw drinking.