Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 7: Problem 17

What are the forces acting on a vertically moving parcel of air? How are they affected by the density of the air parcel?

Short Answer

Expert verified
The forces acting on a vertically moving air parcel are gravity and buoyancy. As the air parcel's density increases, the gravitational force on it also increases, while the buoyancy force depends on the density difference between the parcel and the surrounding air. If the parcel is denser than the surrounding air, the buoyancy force acts downwards - and if it's less dense, it acts upwards.

Step by step solution

01

Identify the Forces

When a parcel of air is moving vertically, there are two forces that come into play: gravity and buoyancy. Gravity always acts downwards, pulling the air parcel towards the Earth, while buoyancy can either act upwards or downwards, depending on the density of the air parcel and the air surrounding it.
02

Understand Gravity's Role

Gravity pulls the air parcel towards the Earth with a force proportional to the mass of the air parcel. Since the mass of air is directly related to its density (density = mass/volume), the force due to gravity increases as the density of the air parcel increases.
03

Understand Buoyancy's Role

Buoyancy force acts in the opposite direction of gravity, and its magnitude is determined by the difference in density between the air parcel and the surrounding air. If the air parcel is denser than the surrounding air, the buoyancy force acts downwards, adding to the force of gravity. If the air parcel is less dense than the surrounding air, the buoyancy force acts upwards, counteracting the force of gravity.
04

Summarize Density's Impact

Thus, as the density of the air parcel increases, the force of gravity increases, pulling the air parcel towards the Earth more strongly. Meanwhile, the buoyancy force either adds to gravity (if the air parcel is denser than the surrounding air) or counteracts it (if the air parcel is less dense), depending on the density difference. So, in total the forces acting on the air parcel and their directions are significantly influenced by its density.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Differentiate between stability and instability relative to a parcel of air rising vertically in the atmosphere.

Describe the locations of Earth's water, both oceanic and fresh. What is the largest repository of freshwater at this time? In what ways is this distribution of water significant to modern society?

If the quantity of water on Earth has been quite constant in volume for at least 2 billion years, how can sea level have fluctuated? Explain.

Describe the occurrence of fog in the United States and Canada. Where are the regions of highest incidence?

How do the adiabatic rates of heating or cooling in a vertically displaced air parcel differ from the normal lapse rate and environmental lapse rate?
See all solutions

Recommended explanations on Geography Textbooks

Glaciated Landscapes

Read Explanation

Geographical Skills

Read Explanation

Diverse Places

Read Explanation

Challenges In The Human Environment

Read Explanation

Migration and Identity

Read Explanation

Water Cycle

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free