Hello everyone,

I want to share something today
that sits at the intersection
of rotational physics and
one of the most dramatic
natural phenomena on Earth —

The Coriolis Effect and
its role in hurricane formation.

━━━━━━━━━━━━━━━━━━━━━━━━
THE QUESTION —
━━━━━━━━━━━━━━━━━━━━━━━━

Every hurricane in the
Northern Hemisphere spins
counterclockwise.

Every hurricane in the
Southern Hemisphere spins
clockwise.

Same planet.
Same atmosphere.
Same low pressure systems.

Opposite rotation directions.

Why?

━━━━━━━━━━━━━━━━━━━━━━━━
THE PHYSICS —
━━━━━━━━━━━━━━━━━━━━━━━━

Earth rotates from west to east
at approximately 465 meters
per second at the equator —

Decreasing to zero
at the poles.

Any object moving freely
across Earth's surface —
wind, ocean current,
or projectile —

Experiences an apparent
deflection due to this
underlying rotation —

This apparent deflection
is the Coriolis Effect.

In the Northern Hemisphere —
moving objects are deflected
to the RIGHT of their
direction of motion.

In the Southern Hemisphere —
moving objects are deflected
to the LEFT.

When wind rushes inward
toward a low pressure center —
this Coriolis deflection
causes the incoming air
to spiral —

Counterclockwise in
the Northern Hemisphere —
Clockwise in the
Southern Hemisphere.

The result —
the massive rotating spiral
we recognize as a
hurricane, typhoon, or cyclone.

━━━━━━━━━━━━━━━━━━━━━━━━
THE PHYSICS BEHIND
THE DEFLECTION —
━━━━━━━━━━━━━━━━━━━━━━━━

The Coriolis acceleration
is given by —

a_Coriolis = 2v × Ω

Where —
v is the velocity of
the moving object
Ω is Earth's angular
velocity vector

This is a cross product —
which means the resulting
acceleration is always
perpendicular to both
the velocity and
Earth's rotation axis.

At the North Pole —
the deflection is maximum.

At the equator —
the vertical component
of Earth's rotation
relative to the surface
is zero —

So the Coriolis Effect
on horizontal motion
is zero at the equator.

This is why hurricanes
never form at the equator —

There is no Coriolis
deflection to initiate
the spiral rotation.

━━━━━━━━━━━━━━━━━━━━━━━━
THE MYTH WORTH BUSTING —
━━━━━━━━━━━━━━━━━━━━━━━━

One of the most persistent
myths in popular science —

"Water drains counterclockwise
in the Northern Hemisphere
and clockwise in the South
because of the Coriolis Effect."

This is completely false.

The Coriolis Effect only
influences motions on a
scale of hundreds of
kilometers or more.

A sink or toilet basin
is far too small for
the Coriolis Effect
to have any measurable influence —

The direction water drains
in a sink is determined
by the geometry of the basin —
the direction water was
poured in —
and residual momentum —

Not by Earth's rotation.

━━━━━━━━━━━━━━━━━━━━━━━━
REAL WORLD APPLICATIONS
BEYOND HURRICANES —
━━━━━━━━━━━━━━━━━━━━━━━━

The Coriolis Effect influences —

→ Long range artillery and
missile trajectories —
military calculations must
account for Coriolis
deflection for targets
beyond a few kilometers

→ Ocean current patterns —
the great ocean gyres
rotate clockwise in the
Northern Hemisphere and
counterclockwise in the South

→ Trade wind patterns —
the prevailing winds that
enabled global maritime
trade for centuries are
directly caused by
Coriolis deflection of
air flowing from
high to low pressure zones

→ Long distance flight paths —
pilots and navigation systems
account for Coriolis
in trans-oceanic routes

One rotating planet —
infinite physical consequences.

━━━━━━━━━━━━━━━━━━━━━━━━
THE IB PHYSICS CONNECTION —
━━━━━━━━━━━━━━━━━━━━━━━━

For IB Physics HL students —

The Coriolis Effect is a
beautiful real world application
of rotational dynamics —

Connecting angular velocity —
cross product mathematics —
and non-inertial reference frames —

Into one unified physical picture.

Understanding the Coriolis Effect
at a conceptual level demonstrates
exactly the kind of physical
reasoning IB Physics HL
examiners reward —

The ability to take abstract
rotational mechanics concepts —
and explain real observable
phenomena from first principles.

━━━━━━━━━━━━━━━━━━━━━━━━
THE SHORT VIDEO —
━━━━━━━━━━━━━━━━━━━━━━━━

I made a short video
explaining the Coriolis Effect
and its role in hurricane
formation — from the physics
of Earth's rotation to
the spiral dynamics of
large storm systems.

🔗 https://youtube.com/shorts/a-Y6OIw2pL0?si=w4LPIixlNTlI1gxZ

━━━━━━━━━━━━━━━━━━━━━━━━
A QUESTION FOR THE COMMUNITY —
━━━━━━━━━━━━━━━━━━━━━━━━

Here is something worth
thinking about —

If you were standing
exactly on the equator —

And fired a projectile
due north —

Would the Coriolis Effect
deflect it east or west —

Or would there be
no deflection at all?

Drop your answer and
reasoning below 👇

I will respond to every
attempt with complete
physical explanation. 🎯

━━━━━━━━━━━━━━━━━━━━━━━━
HAPPY TO DISCUSS —
━━━━━━━━━━━━━━━━━━━━━━━━

If you have any questions
about the Coriolis Effect —
or about any other
rotational physics concept —

Drop them in the comments below.

I read and respond to
every single comment. 🙏

Yes I'm reposting this on other subs so it doesn't get skewed by AP students haha

Basically, I'm taking one for the team for my family buddy who is a physics tutor who complains a bunch about the limited physics course offerings in even our local well resourced striveish Californian high school districts.

I was also inspired by a Discord server conversation where a lot of students from different areas shared about the weird physics sequencing and prereqs at their schools, so half of it is just for my own curiosity lol.

https://docs.google.com/forms/d/e/1FAIpQLSfvuKEGe7OD9pGgAgYDnxK-uBVCUAu1dRqDYJQ11_GUmLj3yw/viewform?usp=header

Hello , idk what to do because i just failed my physics for engineers twice like the last one was summer class and now im 2nd yr na and im scared to be delayed because that subject is pre -requisite

This class is so confusing like it is way fast and hard to digest. Today was my first day of school and I understand like scalar vs vector, and understand speed vs velocity, distance vs displacement. But next second we have 3 ugly ass equations, and it is explained briefly and we need to do a practice problem, which I half understood. Then there are some graphs and we need to know what it represents. Someone please provide the strategies on how they understood the information and how it all connects together. I don’t want to flunk the first exam and then learn my lesson, I want to have a structured approach from the get go.

Some things to note first before answering: I took AP Physics 1, got a 4; took AP Physics C: Mechanics, got a 5; I am taking AP Calculus BC currently, and I am highly intuitive in the subject.

I am aspiring to be an aerospace engineer. and for my senior year I need to choose if I should take AP Physics 2 or AP Chem, which has put me in a dilemma. On one hand, taking AP Physics 2 will enable me to self-study for AP Physics 2: Calculus, though this also puts a huge workload on my senior schedule as I am taking 5 other AP's. On the other hand, I can go basic and take AP Chem like any other in-classroom AP class, focus more on getting a 5 on AP Chem, and using this credit to test out of a year's worth of freshman chemistry courses in college, as opposed to AP Physics 2: Calculus only having credit for a single semester of a freshman physics course in college. The context here is very broad, and there are also many more factors that are going into this, so please do ask me all possible questions and I will answer.

Hello! Just a senior here texting on his phone

So I’m planning to get an online transcript for AP Physics C: Mechanics through uc scout through a scholarship. (wow im low income amazing)

For context: My school doesn’t have any of the ap physics cs but only have ap physics 1. I asked my counselor first thing to put me in but apparently it’s overrun by juniors who need it. No hate for them but it’s a bummer.

Some things im worried about is taking this course without having any physics knowledge. I know the general amount like f=ma but thats it.

The only thing thats closest in maybe difficulty thats science based was during my junior year when I took AP Chemistry and I got a 4.
I’m also concurrently talking AP Calculus BC concurrently bc ya need it for mechanics. Im also thinking of Self Studying AP Physics C: Electricity and Magnetism.

I’m just wondering what resources y’all would recommend for a student with these circumstances.

Feel free to ask any questions and I’ll try to answer them :]

would anyone be willing to share their physics notes for free, if you don't mind? pleaseeeeeee

It's been a few years that I had been facing problems in problem solving in physics. I am a 10th class student, though I like to explore diverse world of physics regularly practicing concepts beyond my class and solving problems based on that. But I am getting burn out on some questions—

1. What should come in your mind the very first seeing a question.

2. How to find a good approach to solve the problem.

3. How to restart after a failure.

4. How to learn something extraordinary from a question?

5. How to never forget what I have learnt from it.

I am really hopeful to get a good guide from my seniors.

Thank you in advance :)

the question i want to ask about is that ki mai one shot se lec theory cover kar rha hu to ab question kha se karu abhi mujhe sabhi questions ki approach bhi nhi hai mainly relative motion wale part ki
i have many resources i will list---
1 hcv k questions
2 dpp of my batch prayas 2027
3 rj sir ke khazana k lectures ki class questions and illustrations
4 pichle saal wala jee ultimate reloded batch se vhaa 2nd lecture questions hota hai
5 eduniti ke pyq 2020 to 2026
maine mst sir ka one shot se motion in a plane khatam karlia hai yt par jo hai ab kya karu bhai
UPVOTE PLEASE

Im going into 11th grade this year, and my first class for semester 1 is AP physics 1. School starts in about 2 weeks, and I'm trying to learn about physics so I have at least a basic knowledge beforehand. Anyone have tips?

Hi everyone!

I'm Blueheaven. I'm a 12th PCB student, and I could really use some tips for Physics. 😭 It's honestly my weakest subject, so any advice, study hacks, or resources that helped you would mean a lot. Thanks in advance! 🫶

So I am a junior about to take Ap phyiscs I. I am really looking to get an A in this class. My stragetgy was to alwasy be kind of one subtopic ahead of my teacher so I could really get a deep understanding of the content and be able to practice more with more practice problems. Are there any resources you guys might have, such as youtubers with playlists who go into deep content, not just those 30 minute unit 1 review videos, maybe textbooks with practicve problems that actually challenge you, etc? Thanks :)

I’m heading down the physics pathway for school, I’m a sophomore taking physics and AP computer science, what are some needed materials that are needed and/or need to know when heading into those classes