Math & Physics

𝐅𝐑𝐎𝐌 𝐑𝐎𝐂𝐊𝐄𝐓𝐒 𝐓𝐎 𝐑𝐎𝐓𝐀𝐓𝐈𝐍𝐆 𝐒𝐓𝐀𝐑𝐒
𝐓𝐇𝐄 𝐔𝐍𝐈𝐕𝐄𝐑𝐒𝐀𝐋 𝐏𝐎𝐖𝐄𝐑 𝐎𝐅 𝐌𝐎𝐌𝐄𝐍𝐓𝐔𝐌 𝐂𝐎𝐍𝐒𝐄𝐑𝐕𝐀𝐓𝐈𝐎𝐍

One of the most fundamental and universally applicable principles in physics is the Law of Conservation of Momentum.
This principle exists in two distinct forms: linear momentum conservation and angular momentum conservation.
Both formulations describe the invariant behavior of physical systems under isolated conditions and provide the theoretical foundation for understanding a wide range of phenomena observed in both everyday experiences and advanced scientific contexts.

1. Conservation of Linear Momentum

Linear momentum is the combination of an object’s mass and velocity.
If no external forces act on a system, the total linear momentum stays the same before and after any interaction.
This is why a gun kicks backward when it fires a bullet. The bullet moves forward, and the gun moves backward, balancing the total momentum (Newton’s third law of motion)

We express this with the equation:

m1 × v1 + m2 × v2 = m1 × v1’ + m2 × v2’

Here, m stands for mass, v for velocity, and the prime symbols (’) mean “after the interaction.”
If no external forces are acting, the total on the left (before) must equal the total on the right (after).

Rockets use the same principle in space.
They throw exhaust gases backward, and by doing so, they move forward — even without air. This is momentum conservation in action!

2. Conservation of Angular Momentum

Now let’s move from straight-line motion to rotational motion. Angular momentum depends on how the mass is spread out and how fast something is spinning.
You’ve probably seen a figure skater start rotating or spinning slowly with arms stretched out and then speed up dramatically by pulling their arms in. What’s going on?

The total angular momentum stays constant if no external torque acts on the skater.
This means:

I × w = constant

Here, I is the moment of inertia (which depends on how the mass is distributed), and w (omega) is the spin rate or angular velocity. If the skater pulls in their arms, I becomes smaller, so w must increase to keep the product the same. That’s why the spin gets faster!

This principle also explains why some stars, when they collapse into neutron stars, rotates hundreds of times per second.
As the star’s size shrinks, its rotation speeds up to conserve angular momentum- just like the skater, but on a cosmic scale.

Best wishes
Sondre Sundrønning

𝐓𝐡𝐞 𝐩𝐡𝐲𝐬𝐢𝐜𝐬 𝐛𝐞𝐡𝐢𝐦𝐝 𝐚 𝐩𝐞𝐧𝐝𝐮𝐥𝐮𝐦



Let’s look at the physics of a pendulum- a simple yet interesting example of harmonic motion.
From antique clocks to playground swings, pendulums show us beautiful laws of motion in action.
But what actually happens as it swings back and forth?
Let’s look at the science- and we’ll even calculate real values using a 15 kg pendulum!

𝐖𝐡𝐚𝐭 𝐢𝐬 𝐚 𝐩𝐞𝐧𝐝𝐮𝐥𝐮𝐦?
A simple pendulum consists of a mass (called the bob) suspended from a fixed point by a string or rod, allowed to swing freely under the influence of gravity.
The physics involves kinetic energy, potential energy, and conservation of energy.

𝐀𝐬 𝐭𝐡𝐞 𝐩𝐞𝐧𝐝𝐮𝐥𝐮𝐦 𝐬𝐰𝐢𝐧𝐠𝐬:

𝑨𝒕 𝒊𝒕𝒔 𝒉𝒊𝒈𝒉𝒆𝒔𝒕 𝒑𝒐𝒊𝒏𝒕, 𝒊𝒕 𝒉𝒂𝒔 𝒎𝒂𝒙𝒊𝒎𝒖𝒎 𝒑𝒐𝒕𝒆𝒏𝒕𝒊𝒂𝒍 𝒆𝒏𝒆𝒓𝒈𝒚, 𝒕𝒉𝒆 𝒌𝒊𝒏𝒆𝒕𝒊𝒄 𝒆𝒏𝒆𝒓𝒈𝒚 𝒊𝒔 𝒛𝒆𝒓𝒐.

𝑨𝒕 𝒊𝒕𝒔 𝒍𝒐𝒘𝒆𝒔𝒕 𝒑𝒐𝒊𝒏𝒕, 𝒊𝒕 𝒉𝒂𝒔 𝒎𝒂𝒙𝒊𝒎𝒖𝒎 𝒌𝒊𝒏𝒆𝒕𝒊𝒄 𝒆𝒏𝒆𝒓𝒈𝒚 𝒂𝒏𝒅 𝒕𝒉𝒆 𝒑𝒐𝒕𝒆𝒏𝒕𝒊𝒂𝒍 𝒆𝒏𝒆𝒓𝒈𝒚 𝒊𝒔 𝒛𝒆𝒓𝒐

𝐓𝐡𝐞 𝐩𝐡𝐲𝐬𝐢𝐜𝐬
We’ll analyze the pendulum using basic mechanics:
• m = mass of the bob
• g = gravitational acceleration (9.81 m/s²)
• h = vertical height from the lowest point
• v = velocity
• PE = potential energy = m * g * h
• KE = kinetic energy = 0.5 * m * v²

𝐌𝐚𝐭𝐡𝐞𝐦𝐚𝐭𝐢𝐜𝐚𝐥 𝐞𝐱𝐚𝐦𝐩𝐥𝐞
Let’s say we pull a 15 kg pendulum bob to a height of 1.2 meters above its lowest point and release it. We’ll calculate its potential energy at the top, velocity at the bottom, and kinetic energy at the bottom.

𝐒𝐭𝐞𝐩 𝟏: 𝐏𝐨𝐭𝐞𝐧𝐭𝐢𝐚𝐥 𝐞𝐧𝐞𝐫𝐠𝐲 𝐚𝐭 𝐭𝐡𝐞 𝐭𝐨𝐩.
PE = m * g * h
PE = 15 kg * 9.81 m/s² * 1.2 m
PE = 176.58 joules

So, at the top of the swing, the pendulum has 176.58 J of potential energy.

𝐒𝐭𝐞𝐩 𝟐: 𝐕𝐞𝐥𝐨𝐜𝐢𝐭𝐲 𝐚𝐭 𝐭𝐡𝐞 𝐛𝐨𝐭𝐭𝐨𝐦
By conservation of energy, all that potential energy turns into kinetic energy at the bottom. So we set:

KE = PE = 176.58 J
But KE = 0.5 * m * v²
So,

176.58 = 0.5 * 15 * v²
176.58 = 7.5 * v²
v² = 176.58 / 7.5
v² = 23.544
v = sqrt(23.544)
v ≈ 4.85 m/s

So, the velocity of the pendulum at the bottom is approximately 4.85 m/s.

𝐒𝐭𝐞𝐩 𝟑: 𝐊𝐢𝐧𝐞𝐭𝐢𝐜 𝐞𝐧𝐞𝐫𝐠𝐭 𝐚𝐭 𝐭𝐡𝐞 𝐛𝐨𝐭𝐭𝐨𝐦
KE = 0.5 * m * v²
KE = 0.5 * 15 * (4.85)²
KE = 7.5 * 23.5225
KE ≈ 176.42 joules

(The slight difference from the earlier PE is due to rounding.)

𝐒𝐮𝐦𝐦𝐚𝐫𝐲

This is a perfect demonstration of how energy is conserved.
The pendulum starts with potential energy, which transforms into kinetic energy as it swings down, and then back into potential energy as it rises.

If you ignore air resistance and friction at the axis, the pendulum would keep swinging forever- just as ideal physics predicts. In real life, energy is gradually lost to friction and air drag, but the principles still apply.

Best wishes
Sondre Sundrønning

𝐀 𝐇𝐘𝐃𝐑𝐎𝐆𝐄𝐍 𝐁𝐎𝐌𝐁 𝐈𝐒 𝐁𝐀𝐒𝐈𝐂𝐀𝐋𝐋𝐘 𝐀 𝐒𝐓𝐀𝐑



The hydrogen bomb, or thermonuclear weapon, is not just a scaled-up atomic bomb. It’s something entirely different. It’s a man-made miniature star, and terrifyingly designed to be dropped on a city.

At the center of this technology is the Teller–Ulam design, a brilliant but also deeply dangerous innovation in physics. Here’s how it works:

𝐒𝐭𝐚𝐠𝐞 𝟏: 𝐓𝐡𝐞 𝐭𝐫𝐢𝐠𝐠𝐞𝐫
A regular atomic bomb (fission bomb) detonates first — this is the same type of bomb that was used on Hiroshima and Nagasaki. But unlike these bombs the fission process is only the beginning.

𝐒𝐭𝐚𝐠𝐞 𝟐: 𝐑𝐚𝐝𝐢𝐚𝐭𝐢𝐨𝐧 𝐈𝐦𝐩𝐥𝐨𝐬𝐢𝐨𝐧
The blast from the fission bomb generates an enormous burst of X-rays, which are trapped and reflected within a special radiation case.
These X-rays don’t explode the second stage- they compress it by using radiation pressure.
This is the core of the Teller–Ulam idea: using pure light to crush the fuel, not just brute force.

𝐒𝐭𝐚𝐠𝐞 𝟑: 𝐓𝐡𝐞 𝐟𝐮𝐬𝐢𝐨𝐧 𝐫𝐞𝐚𝐜𝐭𝐢𝐨𝐧
Inside the second stage is lithium deuteride- a fusion fuel.
The intense heat and pressure cause it to generate tritium, which fuses with deuterium in reactions that release neutrons and enormous energy- exactly the kind of reaction that powers the Sun and all other stars.

𝐒𝐭𝐚𝐠𝐞 𝟒: 𝐅𝐢𝐧𝐚𝐥 𝐟𝐢𝐬𝐬𝐢𝐨𝐧
The fast neutrons from the fusion stage split a surrounding shell of uranium, adding even more explosive energy and radioactive fallout.

This means a hydrogen bomb doesn’t just explode- it «ignites» like a star.
In the microseconds after detonation, it actually behaves like a stellar core: atoms fuse, temperatures reach tens of millions of degrees- and energy is unleashed in proportions that defy comprehension.

And unlike stars, which are born in nebulae and shine for billions of years, this star is made to last for less than a second- and destroy everything around it.

𝐒𝐜𝐢𝐞𝐧𝐜𝐞 𝐟𝐚𝐜𝐭
A fusion bomb creates the same kind of nuclear reaction that occurs in the Sun. In theory- and practice- it’s a tiny, artificial star, packaged in steel, and deliverable by missile or aircraft.

𝐁𝐞𝐬𝐭 𝐰𝐢𝐬𝐡𝐞𝐬
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𝐇𝐎𝐖 𝐀 𝐑𝐎𝐂𝐊𝐄𝐓 𝐋𝐀𝐔𝐍𝐂𝐇 𝐃𝐄𝐅𝐈𝐄𝐒 𝐆𝐑𝐀𝐕𝐈𝐓𝐘?



When you watch a rocket launch, it almost seems like magic: a giant machine, weighing hundreds or even thousands of tons, lifting off the ground and soaring into space.
But there is no magic involved- only the precise application of physics and mathematics.

A rocket launch begins with the fundamental challenge of overcoming gravity.
Gravity is the force that attracts every object toward the center of the Earth.
The strength of this force on an object is called its weight, and it is calculated by the simple formula:

𝑾𝒆𝒊𝒈𝒉𝒕 = 𝒎𝒂𝒔𝒔 𝒙 𝒈𝒓𝒂𝒗𝒊𝒕𝒂𝒕𝒊𝒐𝒏𝒂𝒍 𝒂𝒄𝒄𝒆𝒍𝒆𝒓𝒂𝒕𝒊𝒐𝒏

In this formula,
• mass is the amount of matter in the object (measured in kilograms),
• gravitational acceleration (often denoted by the letter “g”) is approximately 9.81 meters per second squared on Earth’s surface.

For example, if a rocket has a mass of 500,000 kilograms, its weight at the surface of the Earth is:

Weight = 500,000 × 9.81 = 4,905,000 newtons

This means the Earth is pulling down on the rocket with a force of nearly five million newtons!

𝐇𝐨𝐰 𝐝𝐨𝐞𝐬 𝐭𝐡𝐞 𝐫𝐨𝐜𝐤𝐞𝐭 𝐟𝐢𝐠𝐡𝐭 𝐛𝐚𝐜𝐤?

Here enters thrust, the force generated by the rocket’s engines. According to Newton’s Third Law of Motion, every action produces an equal and opposite reaction.
When a rocket engine expels high-speed exhaust gases downward, the reaction force pushes the rocket upward.

For a rocket to lift off, the thrust it generates must be greater than the weight pulling it down. Mathematically:

𝑻𝒉𝒓𝒖𝒔𝒕 > 𝒎𝒂𝒔𝒔 𝒙 𝒈𝒓𝒂𝒗𝒊𝒕𝒂𝒕𝒊𝒏𝒂𝒍 𝒂𝒄𝒄𝒆𝒍𝒆𝒓𝒂𝒕𝒊𝒐𝒏

If thrust is less than weight, the rocket stays grounded. If thrust equals weight, the rocket hovers but doesn’t rise.
Only when thrust exceeds weight does the rocket accelerate upwards.

The rocket’s net force at any moment is given by:

𝑵𝒆𝒕 𝒇𝒐𝒓𝒄𝒆 = 𝒕𝒉𝒓𝒖𝒔𝒕 - 𝒘𝒆𝒊𝒈𝒉𝒕
And according to Newton’s Second Law of Motion:

𝑨𝒄𝒄𝒆𝒍𝒆𝒓𝒂𝒕𝒊𝒐𝒏 = 𝒏𝒆𝒕 𝒇𝒐𝒓𝒄𝒆 / 𝒎𝒂𝒔𝒔
The acceleration the rocket experiences is directly proportional to the excess thrust after overcoming its own weight.

If we plug in real numbers, let’s say the rocket generates 6,000,000 newtons of thrust. The net force would be:

Net force = 6,000,000 - 4,905,000 = 1,095,000 newtons

The acceleration at liftoff would then be:

Acceleration = 1,095,000 / 500,000 = 2.19 meters per second squared

This means that initially, the rocket accelerates upward at a little over 2 meters per second every second- slow at first, but it quickly builds momentum.

Fuel, mass, and the tyranny of the rocket equation

One of the biggest challenges is that rockets are extremely heavy at launch- and most of that weight is fuel.
As the engines burn fuel, the rocket becomes lighter.
This dramatically affects the rocket’s acceleration over time.

The relationship between mass loss and rocket acceleration is described by the Tsiolkovsky Rocket Equation, which is a fundamental formula in astronautics:

Change in velocity (delta-v) = exhaust velocity × natural logarithm of (initial mass / final mass)

Where:
• exhaust velocity is the speed at which gases are expelled from the rocket nozzle,
• initial mass includes the rocket plus all its fuel,
• final mass is the rocket after burning fuel.

The natural logarithm (ln) function shows that even burning a lot of fuel only increases speed gradually. This is why rockets are built in stages: to shed dead weight once a stage’s fuel is depleted, making the remaining vehicle much lighter and more efficient.

Without staging, a rocket would have to carry so much extra fuel to lift its own fuel that it would quickly become impractically massive. Each stage allows the rocket to “reset” the mass ratio and accelerate more effectively.

𝐖𝐡𝐲 𝐝𝐨 𝐫𝐨𝐜𝐤𝐞𝐭𝐬 𝐭𝐢𝐥𝐭 𝐚𝐟𝐭𝐞𝐫 𝐥𝐚𝐮𝐧𝐜𝐡?

At liftoff, rockets go straight up, but very soon they start to tilt sideways. This maneuver, called the gravity turn, serves two purposes:
1. It conserves fuel by allowing gravity itself to help curve the flight path.
2. It builds up horizontal velocity necessary for orbit.

To stay in a stable orbit around Earth, a spacecraft must reach a tremendous horizontal speed. For low Earth orbit, this speed is about 7.8 kilometers per second, or roughly 28,000 kilometers per hour.

Thus, the goal of a rocket is not just to go “up” but to achieve enough sideways speed to continuously “fall around” Earth rather than back down into it. In orbit, the spacecraft is still under the influence of gravity- it is falling- but because it moves forward fast enough, the ground curves away at the same rate as it falls.

𝐒𝐮𝐦𝐦𝐚𝐫𝐲
• Gravity pulls the rocket down with a force equal to its mass times Earth’s gravitational acceleration.
• The rocket engine produces thrust by expelling gases at high speed.
• To lift off, thrust must be greater than weight.
• As fuel burns, the rocket’s mass decreases, leading to faster acceleration.
• Rockets use staging to shed weight and become more efficient.
• Reaching orbit requires tremendous sideways speed, not just altitude.

Rockets do not truly ‘escape’ gravity- they operate within the framework of physical laws, precisely balancing forces, mass, acceleration, and velocity in a rigorously controlled process that enables their ascent atop high-velocity exhaust into space.

𝐁𝐞𝐬𝐭 𝐰𝐢𝐬𝐡𝐞𝐬
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HOW DOES A PRESSURE COOKER SPPED UP COOKING?



If you ever have used a pressure cooker, you know it can turn tough beans or meat into soft, tender meals incredibly fast.
But how exactly does it work- and why is it so much quicker than traditional boiling?

The answer lies in physics, specifically in a powerful relationship called the ideal gas law:

PV = nRT

Where:
• P is the pressure of the gas,
• V is the volume it occupies,
• n is the amount of gas (in moles),
• R is the gas constant,
• T is the temperature (in Kelvin).

In a sealed system (fixed volume), if you increase the pressure (P), the temperature (T) must also rise to satisfy the equation.
This is the secret behind why pressure cookers are so effective!

WHAT HAPPENS INSIDE A PRESSURE COOKER
When you heat a closed pressure cooker:
• Water boils and turns into steam.
• Steam builds up inside because it cannot escape.
• Pressure inside the cooker increases.
• As pressure rises, the boiling point of water rises.
• Water and steam reach temperatures far above 100°C (212°F) — often around 120°C (250°F) or more.

At these higher temperatures, the chemical reactions that cook food happen much faster:
• Fibers break down quicker,
• Proteins denature faster,
• Starches soften rapidly.

Higher pressure leads to higher temperature, and higher temperature dramatically speeds up cooking.

THE WHOLE PROCESS- STEP BY STEP
1. Heat is applied to the pressure cooker.
2. Water boils, producing steam.
3. Steam is trapped, causing pressure to increase inside.
4. Pressure rise causes boiling point to increase.
5. Higher boiling point means hotter steam and water.
6. Hotter environment cooks food much faster!

SUMMARY
• A pressure cooker uses the relationship PV = nRT to increase the cooking temperature by trapping steam and raising pressure.
• Higher pressure raises the boiling point of water.
• Higher temperatures speed up the chemical reactions that cook food.
• As a result, meals are ready in a fraction of the usual time!

Best Wishes
Sondre Sundrønning

Why Do Black Clothes Feel Hotter in the Sun- and White Clothes Feel Cooler?



Have you ever stepped outside on a sunny day wearing a black T-shirt and immediately felt like you were roasting?
Or noticed how wearing a white shirt somehow keeps you much more comfortable under the same sun?
There’s real physics behind this everyday experience- mand it all comes down to how different colors interact with sunlight.

1. How Color Affects Heat Absorption

Sunlight carries energy. When it hits an object, some of that light is absorbed, and some is reflected.
The energy from absorbed light doesn’t just disappear- it gets converted into thermal energy (heat), warming the material.
• Black surfaces absorb almost all the wavelengths of visible light. Very little is reflected away.
• White surfaces, on the other hand, reflect most of the visible light wavelengths and absorb much less.

To summarise:
• Black = absorbs more light = absorbs more energy = heats up quickly.
• White = reflects most light = absorbs little energy = stays cooler.

2. Why You Feel the Difference on Your Skin

When you wear black clothes, the fabric absorbs a lot of sunlight and heats up rapidly.
That heat is then transferred to your skin through conduction (direct contact) and radiation (infrared emission from the hot fabric).
This is why black clothes can feel intensely hot after just a few minutes in the sun.

White clothes, by reflecting most of the sunlight, don’t heat up nearly as much.
As a result, less heat is transferred to your body, and you feel much cooler.

3. It’s Not Just About Color- Material Matters Too

While color plays a major role, the type of fabric also affects how hot you feel:
• Thick, heavy black fabrics can trap heat even more.
• Light, breathable white fabrics not only reflect light but also allow sweat to evaporate, providing additional cooling through evaporative cooling.

This is why desert cultures traditionally wear loose, white clothing- it maximizes reflection of sunlight and promotes airflow around the body.

Summary:
• Black clothes feel hotter in the sun because they absorb nearly all incoming sunlight and convert it into heat.
• White clothes feel cooler because they reflect most of the sunlight, absorbing very little energy and thus staying cooler.

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Best wishes
Sondre Sundrønning

𝐀𝐫𝐜𝐡𝐢𝐦𝐞𝐝𝐞𝐬 𝐏𝐫𝐢𝐧𝐜𝐢𝐩𝐥𝐞
𝐖𝐡𝐲 𝐝𝐨 𝐨𝐛𝐣𝐞𝐜𝐭𝐬 𝐟𝐥𝐨𝐚𝐭 𝐨𝐫 𝐬𝐢𝐧𝐤 𝐢𝐧 𝐰𝐚𝐭𝐞𝐫?



ʜᴀᴠᴇ ʏᴏᴜ ᴇᴠᴇʀ ᴅʀᴏᴘᴘᴇᴅ ꜱᴏᴍᴇᴛʜɪɴɢ ɪɴᴛᴏ ᴀ ᴘᴏᴏʟ ᴀɴᴅ ɴᴏᴛɪᴄᴇᴅ ᴛʜᴀᴛ ꜱᴏᴍᴇ ᴏʙᴊᴇᴄᴛꜱ ꜰʟᴏᴀᴛ ᴡʜɪʟᴇ ᴏᴛʜᴇʀꜱ ꜱɪɴᴋ? ᴘᴇʀʜᴀᴘꜱ ᴀ ʙᴇᴀᴄʜ ʙᴀʟʟ ʙᴏᴜɴᴄᴇꜱ ʙᴀᴄᴋ ᴛᴏ ᴛʜᴇ ꜱᴜʀꜰᴀᴄᴇ, ᴡʜɪʟᴇ ᴀ ꜱᴏʟɪᴅ ʀᴜʙʙᴇʀ ʙᴀʟʟ ᴏʀ ᴀ ʜᴇᴀᴠʏ ꜱᴛᴏɴᴇ ꜱɪɴᴋꜱ ꜱᴛʀᴀɪɢʜᴛ ᴛᴏ ᴛʜᴇ ʙᴏᴛᴛᴏᴍ. ᴡʜᴀᴛ ᴄᴀᴜꜱᴇꜱ ᴛʜɪꜱ ᴅɪꜰꜰᴇʀᴇɴᴄᴇ? ᴡʜᴀᴛ ɪꜱ ʜᴀᴘᴘᴇɴɪɴɢ ʙᴇɴᴇᴀᴛʜ ᴛʜᴇ ꜱᴜʀꜰᴀᴄᴇ?

ᴛᴏ ᴀɴꜱᴡᴇʀ ᴛʜɪꜱ, ᴡᴇ ᴛᴜʀɴ ᴛᴏ ᴀ ʙʀɪʟʟɪᴀɴᴛ ɪᴅᴇᴀ ꜰᴏʀᴍᴜʟᴀᴛᴇᴅ ᴏᴠᴇʀ 2,000 ʏᴇᴀʀꜱ ᴀɢᴏ: ᴀʀᴄʜɪᴍᴇᴅᴇꜱ’ ᴘʀɪɴᴄɪᴘʟᴇ.
ᴛʜɪꜱ ᴘʀɪɴᴄɪᴘʟᴇ ɴᴏᴛ ᴏɴʟʏ ᴇxᴘʟᴀɪɴꜱ ᴡʜʏ ᴄᴇʀᴛᴀɪɴ ᴏʙᴊᴇᴄᴛꜱ ꜰʟᴏᴀᴛ, ʙᴜᴛ ᴀʟꜱᴏ ᴘʀᴏᴠɪᴅᴇꜱ ᴀ ᴘᴏᴡᴇʀꜰᴜʟ ᴛᴏᴏʟ ꜰᴏʀ ᴜɴᴅᴇʀꜱᴛᴀɴᴅɪɴɢ ʜᴏᴡ ꜰᴏʀᴄᴇꜱ ᴀᴄᴛ ᴡɪᴛʜɪɴ ꜰʟᴜɪᴅꜱ ʟɪᴋᴇ ᴡᴀᴛᴇʀ.

𝐀𝐫𝐜𝐡𝐢𝐦𝐞𝐝𝐞𝐬 𝐏𝐫𝐢𝐧𝐜𝐢𝐩𝐥𝐞 𝐢𝐧 𝐬𝐢𝐦𝐩𝐥𝐞 𝐭𝐞𝐫𝐦𝐬

ᴡʜᴇɴ ᴀɴ ᴏʙᴊᴇᴄᴛ ɪꜱ ꜱᴜʙᴍᴇʀɢᴇᴅ ɪɴ ᴀ ꜰʟᴜɪᴅ (ꜱᴜᴄʜ ᴀꜱ ᴡᴀᴛᴇʀ), ɪᴛ ᴇxᴘᴇʀɪᴇɴᴄᴇꜱ ᴀɴ ᴜᴘᴡᴀʀᴅ ꜰᴏʀᴄᴇ ᴋɴᴏᴡɴ ᴀꜱ ᴛʜᴇ ʙᴜᴏʏᴀɴᴛ ꜰᴏʀᴄᴇ.
ᴛʜᴇ ᴍᴀɢɴɪᴛᴜᴅᴇ ᴏꜰ ᴛʜɪꜱ ꜰᴏʀᴄᴇ ɪꜱ ᴇxᴀᴄᴛʟʏ ᴇQᴜᴀʟ ᴛᴏ ᴛʜᴇ ᴡᴇɪɢʜᴛ ᴏꜰ ᴛʜᴇ ꜰʟᴜɪᴅ ᴛʜᴀᴛ ᴛʜᴇ ᴏʙᴊᴇᴄᴛ ᴅɪꜱᴘʟᴀᴄᴇꜱ.

ʙᴜᴏʏᴀɴᴛ ꜰᴏʀᴄᴇ = ᴡᴇɪɢʜᴛ ᴏꜰ ᴅɪꜱᴘʟᴀᴄᴇᴅ ᴡᴀᴛᴇʀ

ᴛʜᴇ ꜰᴀᴛᴇ ᴏꜰ ᴛʜᴇ ᴏʙᴊᴇᴄᴛ- ᴡʜᴇᴛʜᴇʀ ɪᴛ ꜰʟᴏᴀᴛꜱ ᴏʀ ꜱɪɴᴋꜱ- ᴅᴇᴘᴇɴᴅꜱ ᴏɴ ʜᴏᴡ ᴛʜɪꜱ ʙᴜᴏʏᴀɴᴛ ꜰᴏʀᴄᴇ ᴄᴏᴍᴘᴀʀᴇꜱ ᴛᴏ ᴛʜᴇ ᴏʙᴊᴇᴄᴛ’ꜱ ᴏᴡɴ ᴡᴇɪɢʜᴛ.

𝐖𝐡𝐲 𝐝𝐨𝐞𝐬 𝐚𝐧 𝐨𝐛𝐣𝐞𝐜𝐭 𝐟𝐥𝐨𝐚𝐭 𝐨𝐫 𝐬𝐢𝐧𝐤?
• ɪꜰ ᴛʜᴇ ᴏʙᴊᴇᴄᴛ ᴡᴇɪɢʜꜱ ʟᴇꜱꜱ ᴛʜᴀɴ ᴛʜᴇ ᴡᴀᴛᴇʀ ɪᴛ ᴅɪꜱᴘʟᴀᴄᴇꜱ, ᴛʜᴇ ʙᴜᴏʏᴀɴᴛ ꜰᴏʀᴄᴇ ɪꜱ ꜱᴛʀᴏɴɢᴇʀ ᴛʜᴀɴ ᴛʜᴇ ᴘᴜʟʟ ᴏꜰ ɢʀᴀᴠɪᴛʏ, ᴀɴᴅ ᴛʜᴇ ᴏʙᴊᴇᴄᴛ ꜰʟᴏᴀᴛꜱ.
• ɪꜰ ᴛʜᴇ ᴏʙᴊᴇᴄᴛ ᴡᴇɪɢʜꜱ ᴍᴏʀᴇ ᴛʜᴀɴ ᴛʜᴇ ᴅɪꜱᴘʟᴀᴄᴇᴅ ᴡᴀᴛᴇʀ, ɢʀᴀᴠɪᴛʏ ᴡɪɴꜱ, ᴀɴᴅ ᴛʜᴇ ᴏʙᴊᴇᴄᴛ ꜱɪɴᴋꜱ.

ᴀᴛ ᴛʜᴇ ᴄᴏʀᴇ ᴏꜰ ᴛʜɪꜱ ʙᴇʜᴀᴠɪᴏʀ ɪꜱ ᴅᴇɴꜱɪᴛʏ, ᴡʜɪᴄʜ ɪꜱ ᴅᴇꜰɪɴᴇᴅ ᴀꜱ ᴍᴀꜱꜱ ᴅɪᴠɪᴅᴇᴅ ʙʏ ᴠᴏʟᴜᴍᴇ:

ᴅᴇɴꜱɪᴛʏ = ᴍᴀꜱꜱ / ᴠᴏʟᴜᴍᴇ
• ɪꜰ ᴀɴ ᴏʙᴊᴇᴄᴛ’ꜱ ᴅᴇɴꜱɪᴛʏ ɪꜱ ʟᴇꜱꜱ ᴛʜᴀɴ ᴛʜᴇ ᴅᴇɴꜱɪᴛʏ ᴏꜰ ᴡᴀᴛᴇʀ, ɪᴛ ᴡɪʟʟ ꜰʟᴏᴀᴛ.
• ɪꜰ ᴀɴ ᴏʙᴊᴇᴄᴛ’ꜱ ᴅᴇɴꜱɪᴛʏ ɪꜱ ɢʀᴇᴀᴛᴇʀ ᴛʜᴀɴ ᴛʜᴇ ᴅᴇɴꜱɪᴛʏ ᴏꜰ ᴡᴀᴛᴇʀ, ɪᴛ ᴡɪʟʟ ꜱɪɴᴋ.

𝐄𝐯𝐞𝐫𝐲𝐝𝐚𝐲 𝐄𝐱𝐚𝐦𝐩𝐥𝐞𝐬
• ᴀ ʙᴇᴀᴄʜ ʙᴀʟʟ ꜰʟᴏᴀᴛꜱ ʙᴇᴄᴀᴜꜱᴇ ɪᴛ ɪꜱ ꜰɪʟʟᴇᴅ ᴡɪᴛʜ ᴀɪʀ ᴀɴᴅ ᴍᴀᴅᴇ ᴏꜰ ʟɪɢʜᴛᴡᴇɪɢʜᴛ ᴍᴀᴛᴇʀɪᴀʟꜱ, ɢɪᴠɪɴɢ ɪᴛ ᴀɴ ᴏᴠᴇʀᴀʟʟ ᴅᴇɴꜱɪᴛʏ ᴍᴜᴄʜ ʟᴏᴡᴇʀ ᴛʜᴀɴ ᴛʜᴀᴛ ᴏꜰ ᴡᴀᴛᴇʀ.
• ᴀ ᴍᴀʀʙʟᴇ ꜱɪɴᴋꜱ ʙᴇᴄᴀᴜꜱᴇ ɪᴛ ɪꜱ ᴍᴀᴅᴇ ᴏꜰ ɢʟᴀꜱꜱ ᴏʀ ꜱᴛᴏɴᴇ, ᴍᴀᴛᴇʀɪᴀʟꜱ ᴡɪᴛʜ ᴅᴇɴꜱɪᴛɪᴇꜱ ᴍᴜᴄʜ ɢʀᴇᴀᴛᴇʀ ᴛʜᴀɴ ᴡᴀᴛᴇʀ.
• ᴀ ꜱᴏᴄᴄᴇʀ ʙᴀʟʟ ᴛʏᴘɪᴄᴀʟʟʏ ꜰʟᴏᴀᴛꜱ, ʙᴜᴛ ɪꜰ ɪᴛ ʙᴇᴄᴏᴍᴇꜱ ᴘᴜɴᴄᴛᴜʀᴇᴅ ᴀɴᴅ ꜰɪʟʟꜱ ᴡɪᴛʜ ᴡᴀᴛᴇʀ, ɪᴛꜱ ᴏᴠᴇʀᴀʟʟ ᴅᴇɴꜱɪᴛʏ ɪɴᴄʀᴇᴀꜱᴇꜱ, ᴀɴᴅ ɪᴛ ᴄᴀɴ ᴇᴠᴇɴᴛᴜᴀʟʟʏ ꜱɪɴᴋ.

𝐒𝐮𝐦𝐦𝐚𝐫𝐲
ᴡʜᴇᴛʜᴇʀ ᴀɴ ᴏʙᴊᴇᴄᴛ ꜰʟᴏᴀᴛꜱ ᴏʀ ꜱɪɴᴋꜱ ɪɴ ᴡᴀᴛᴇʀ ᴅᴇᴘᴇɴᴅꜱ ᴏɴ ᴛʜᴇ ʀᴇʟᴀᴛɪᴏɴꜱʜɪᴘ ʙᴇᴛᴡᴇᴇɴ ɪᴛꜱ ᴅᴇɴꜱɪᴛʏ ᴀɴᴅ ᴛʜᴇ ᴅᴇɴꜱɪᴛʏ ᴏꜰ ᴡᴀᴛᴇʀ.
ᴀʀᴄʜɪᴍᴇᴅᴇꜱ’ ᴘʀɪɴᴄɪᴘʟᴇ ꜱʜᴏᴡꜱ ᴛʜᴀᴛ ꜰʟᴏᴀᴛɪɴɢ ɪꜱ ᴛʜᴇ ʀᴇꜱᴜʟᴛ ᴏꜰ ᴀ ʙᴀʟᴀɴᴄᴇ ʙᴇᴛᴡᴇᴇɴ ᴛᴡᴏ ᴄᴏᴍᴘᴇᴛɪɴɢ ꜰᴏʀᴄᴇꜱ: ɢʀᴀᴠɪᴛʏ ᴘᴜʟʟɪɴɢ ᴛʜᴇ ᴏʙᴊᴇᴄᴛ ᴅᴏᴡɴᴡᴀʀᴅ ᴀɴᴅ ʙᴜᴏʏᴀɴᴛ ꜰᴏʀᴄᴇ ᴘᴜꜱʜɪɴɢ ɪᴛ ᴜᴘᴡᴀʀᴅ.

ᴛʜɪꜱ ᴘʀɪɴᴄɪᴘʟᴇ ᴀᴘᴘʟɪᴇꜱ ꜰᴀʀ ʙᴇʏᴏɴᴅ ꜱɪᴍᴘʟᴇ ᴏʙᴊᴇᴄᴛꜱ ɪɴ ᴀ ꜱᴡɪᴍᴍɪɴɢ ᴘᴏᴏʟ. ɪᴛ ᴇxᴘʟᴀɪɴꜱ ᴡʜʏ ᴍᴀꜱꜱɪᴠᴇ ꜱᴛᴇᴇʟ ꜱʜɪᴘꜱ ꜰʟᴏᴀᴛ—ʙᴇᴄᴀᴜꜱᴇ ᴛʜᴇʏ ᴅɪꜱᴘʟᴀᴄᴇ ᴀ ʟᴀʀɢᴇ ᴀᴍᴏᴜɴᴛ ᴏꜰ ᴡᴀᴛᴇʀ ᴡʜᴏꜱᴇ ᴡᴇɪɢʜᴛ ɪꜱ ɢʀᴇᴀᴛᴇʀ ᴛʜᴀɴ ᴛʜᴇ ꜱʜɪᴘ’ꜱ ᴏᴡɴ ᴡᴇɪɢʜᴛ. ɪᴛ ᴀʟꜱᴏ ᴇxᴘʟᴀɪɴꜱ ʜᴏᴡ ꜱᴜʙᴍᴀʀɪɴᴇꜱ ᴄᴏɴᴛʀᴏʟ ᴛʜᴇɪʀ ʙᴜᴏʏᴀɴᴄʏ ᴛᴏ ᴅɪᴠᴇ ᴏʀ ʀᴇꜱᴜʀꜰᴀᴄᴇ ʙʏ ᴀᴅᴊᴜꜱᴛɪɴɢ ᴛʜᴇɪʀ ᴏᴠᴇʀᴀʟʟ ᴅᴇɴꜱɪᴛʏ ᴜꜱɪɴɢ ʙᴀʟʟᴀꜱᴛ ᴛᴀɴᴋꜱ.
ꜰʀᴏᴍ ꜱᴍᴀʟʟ ꜱᴛᴏɴᴇꜱ ᴛᴏ ᴇɴᴏʀᴍᴏᴜꜱ ᴠᴇꜱꜱᴇʟꜱ, ᴛʜᴇ ꜱᴀᴍᴇ ᴛɪᴍᴇʟᴇꜱꜱ ᴘʜʏꜱɪᴄꜱ ɪꜱ ᴀᴛ ᴡᴏʀᴋ.

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Best wishes
Sondre Sundrønning

𝐈𝐟 𝐭𝐡𝐞 𝐒𝐮𝐧 𝐢𝐬 𝐬𝐨 𝐇𝐨𝐭, 𝐰𝐡𝐲 𝐢𝐬 𝐒𝐩𝐚𝐜𝐞 𝐬𝐨 𝐂𝐨𝐥𝐝?



One of the most classic questions that appears deceptively simple at first glance, yet reveals a rich underlying explanation grounded in the principles of thermodynamics, gas solubility, and fluid dynamics.

𝐓𝐡𝐞 𝐒𝐮𝐧: 𝐀 𝐆𝐢𝐚𝐧𝐭 𝐓𝐡𝐞𝐫𝐦𝐨𝐧𝐮𝐜𝐥𝐞𝐚𝐫 𝐅𝐮𝐫𝐧𝐚𝐜𝐞
The Sun’s surface is about 5,500°C (9,932°F), and its core is over 15 million °C.
That’s unimaginably hot! So it’s natural to wonder: if the Sun is pumping out so much energy, why isn’t space hot too?

𝐇𝐞𝐚𝐭 𝐧𝐞𝐞𝐝𝐬 𝐚 𝐦𝐞𝐝𝐢𝐮𝐦 𝐨𝐫 𝐫𝐚𝐝𝐢𝐚𝐭𝐢𝐨𝐧
To answer that, we need to understand how heat travels.

There are three ways to transfer heat:
1. Conduction – through direct contact (like a hot pan on your hand)
2. Convection – through moving fluids (like hot air rising)
3. Radiation – through electromagnetic waves (like sunlight)

Space is a vacuum — there’s no air, no molecules, no “stuff” to transfer heat by conduction or convection.

That leaves only radiation.

SPACE ISN’T COLD THE WAY YOU THINK
When we say “space is cold,” we’re not talking about cold air — there’s essentially no air in space. What we really mean is: if an object is floating out there, it loses heat fast and doesn’t gain much unless it’s directly in sunlight.

So an object in the shadow of Earth, for example, can cool down to -150°C, while one in direct sunlight can heat up to 120°C or more. That’s a huge temperature swing — and it all depends on radiation.

𝐒𝐨 𝐖𝐡𝐲 𝐃𝐨𝐧’𝐭 𝐰𝐞 𝐅𝐞𝐞𝐥 𝐭𝐡𝐞 𝐒𝐮𝐧’𝐬 𝐇𝐞𝐚𝐭 𝐢𝐧 𝐒𝐩𝐚𝐜𝐞?
You would — but only if you’re directly in the sunlight. Astronauts on spacewalks feel intense heat on the sunlit side of their suit and freezing cold in the shade. Their suits have to handle both extremes at once!

Without an atmosphere to spread and hold warmth (like Earth’s does), space doesn’t feel “hot” — even when you’re bathed in solar radiation.

Key Principles to Understand:
• The Sun transfers energy primarily through radiative heat transfer (electromagnetic radiation).
• Outer space is a vacuum, meaning there is no medium (like air or water) to conduct or convect heat.
• Thermal exposure determines temperature: direct sunlight results in intense heating, while shaded regions become extremely cold.
• An object’s temperature in space depends on the dynamic balance between absorbing incoming radiation and emitting thermal radiation back into space.

Best Wishes
Sondre Sundrønning

𝐖𝐇𝐘 𝐃𝐎𝐄𝐒 𝐒𝐎𝐃𝐀 𝐅𝐈𝐙𝐙 𝐌𝐎𝐑𝐄 𝐖𝐇𝐄𝐍 𝐘𝐎𝐔 𝐃𝐑𝐎𝐏 𝐀𝐍 𝐈𝐂𝐄 𝐂𝐔𝐁𝐄 𝐈𝐍𝐓𝐎 𝐈𝐓?



You might have observed that when you drop an ice cube into a glass of soda, the drink suddenly fizzes a lot.
This seemingly simple event actually reveals a rich interplay of physical chemistry- drawing upon gas solubility, surface physics- and equilibrium thermodynamics.

* 𝐓𝐡𝐞 𝐂𝐡𝐞𝐦𝐞𝐬𝐭𝐫𝐲 𝐨𝐟 𝐂𝐚𝐫𝐛𝐨𝐧𝐚𝐭𝐢𝐨𝐧

Soda is carbonated by dissolving carbon dioxide (CO₂) gas under high pressure.
The dissolved gas exists in dynamic equilibrium with its gaseous form and also reacts with water to form carbonic acid:

CO₂(g) ⇌ CO₂(aq)
CO₂(aq) + H₂O ⇌ H₂CO₃ (carbonic acid)

When the bottle or can is opened, the pressure is suddenly released, shifting the equilibrium to the left and allowing CO₂ to escape from the liquid as bubbles.

Even after opening, much of the CO₂ remains temporarily dissolved.
It needs a place to begin forming bubbles- this is where physics comes in.

* 𝐍𝐮𝐜𝐥𝐞𝐚𝐭𝐢𝐨𝐧: 𝐈𝐜𝐞 𝐂𝐮𝐛𝐞𝐚 𝐚𝐬 𝐁𝐮𝐛𝐛𝐥𝐞 𝐅𝐚𝐜𝐭𝐨𝐫𝐢𝐞𝐬
The surface of an ice cube is not perfectly smooth. It contains microscopic crevices, imperfections, and crystalline boundaries that act as nucleation sites. These are the “starting points” where dissolved gas molecules gather and form bubbles.

Also during freezing, tiny air pockets often become trapped within the ice.
When submerged in soda, these air-filled cavities provide even more surfaces for CO₂ to rapidly accumulate and form bubbles.

* 𝐏𝐫𝐞𝐬𝐬𝐮𝐫𝐞 𝐏𝐞𝐫𝐭𝐮𝐫𝐛𝐚𝐭𝐢𝐨𝐧 𝐚𝐧𝐝 𝐋𝐢𝐪𝐮𝐢𝐝 𝐃𝐢𝐬𝐩𝐥𝐚𝐜𝐞𝐦𝐞𝐧𝐭
Dropping an ice cube into the soda displaces liquid and disturbs the local pressure equilibrium. This causes:

A brief drop in pressure around the ice.

Convection currents in the liquid due to the sudden thermal gradient (cold ice vs. warmer soda).

Enhanced transport of CO₂ molecules toward the nucleation sites.

These effects collectively trigger rapid bubble formation and rising fizz.

* 𝐖𝐡𝐚𝐭 𝐀𝐛𝐨𝐮𝐭 𝐒𝐨𝐥𝐮𝐛𝐢𝐥𝐢𝐭𝐲?
One might ask: shouldn’t cold temperatures increase the solubility of CO₂ (according to Henry’s Law) and thereby decrease fizzing?

Yes- in theory, cooler liquids hold more gas.
But solubility equilibrium is not reached instantaneously. The physical disruption and presence of nucleation sites dominate in the short term, leading to more visible bubbling before any cooling effect can suppress it.

* 𝐓𝐡𝐞 𝐌𝐞𝐧𝐭𝐨𝐬 𝐀𝐧𝐚𝐥𝐨𝐠𝐲
This phenomenon shares key characteristics with the famous Mentos and Diet Coke reaction. Mentos candies have a rough, porous surface that offers thousands of nucleation sites per square centimeter. When dropped into soda, they dramatically accelerate the release of CO₂, causing a geyser-like eruption.

Though the ice cube doesn’t produce such an extreme effect, the underlying principle is the same: the more nucleation sites and surface area, the faster gas is liberated.

Summary

When you drop an ice cube into a soda:
• Rough surfaces provide nucleation sites for CO₂ bubbles.
• Trapped air pockets inside the ice amplify the effect.
• Liquid displacement and thermal gradients disrupt equilibrium and mobilize gas.
• Fizzing increases as CO₂ escapes rapidly before new solubility equilibrium is reached.

ɪꜰ ʏᴏᴜ ꜰɪɴᴅ ᴏᴜʀ ᴘᴏꜱᴛꜱ ɪɴᴛᴇʀᴇꜱᴛɪɴɢ, ᴘʟᴇᴀꜱᴇ ᴄᴏɴꜱɪᴅᴇʀ ᴛᴏ ꜰᴏʟʟᴏᴡ ᴛʜɪꜱ ᴘᴀɢᴇ.

ʙᴇꜱᴛ ᴡɪꜱʜᴇꜱ
Sondre Sundrønning
Physicist

WHY ARE SCALARS AND VECTOR QUANTITIES IN REAL LIFE?



Think scalar vs. vector is just classroom stuff? Think again.

Scalars only have magnitude—like temperature (22°C), mass (75 kg), or speed (60 km/h).
Vectors have magnitude and direction- like velocity (60 km/h north), force (50 N downward), or displacement (5 m east).

Here’s why that matters:

1. Driving:
Speed tells you how fast.
Velocity tells you how fast and where you’re going. GPS? That’s vector work.

2. Flying: A plane heading north with wind blowing west?
You need vector math to stay on course.

3. Sports: A soccer kick isn’t just about strength—it’s about the angle too.
Direction matters.

4. Engineering: Building a bridge?
Forces like tension and compression act in specific directions. Get it wrong, and the structure fails.

5. Navigation: “Walk 5 km” is vague. “Walk 5 km north”? Clear. That’s scalar vs. vector in action.

Bottom line: Scalars tell you how much. Vectors tell you how much and which way. And in real life, direction matters.

ɪꜰ ʏᴏᴜ ꜰɪɴᴅ ᴏᴜʀ ᴘᴏꜱᴛꜱ ɪɴᴛᴇʀᴇꜱᴛɪɴɢ, ᴘʟᴇᴀꜱᴇ ᴄᴏɴꜱɪᴅᴇʀ ᴛᴏ ꜰᴏʟʟᴏᴡ ᴛʜɪꜱ ᴘᴀɢᴇ.

ʙᴇꜱᴛ ᴡɪꜱʜᴇꜱ
Sondre Sundrønning

𝐖𝐇𝐀𝐓 𝐖𝐎𝐔𝐋𝐃 𝐇𝐀𝐏𝐏𝐄𝐍 𝐈𝐅 𝐓𝐇𝐄 𝐄𝐀𝐑𝐓𝐇 𝐒𝐔𝐃𝐃𝐄𝐍𝐋𝐘 𝐒𝐓𝐎𝐏𝐏𝐄𝐃 𝐑𝐎𝐓𝐀𝐓𝐈𝐍𝐆 𝐅𝐎𝐑 𝟓 𝐒𝐄𝐂𝐎𝐍𝐃𝐒?



Five seconds may seem insignificant, but the consequences of such an event would be catastrophic.
This scenario results from fundamental principles of rotational dynamics: inertia, angular momentum, and the physics of sudden deceleration.

𝐇𝐎𝐖 𝐅𝐀𝐒𝐓 𝐈𝐒 𝐓𝐇𝐄 𝐄𝐀𝐑𝐓𝐇 𝐑𝐎𝐓𝐀𝐓𝐈𝐍𝐆?
The Earth rotates once every 24 hours, and that means a point on the equator is moving at about 1670 kilometers per hour, or 465 meters per second.

We don’t feel this motion because everything- including the air- is rotating with us at the same speed, the Earths rotation is also constant so Newton’s first law is fulfilled.

𝐖𝐇𝐘 𝐒𝐓𝐎𝐏𝐏𝐈𝐍𝐆 𝐖𝐎𝐔𝐋𝐃 𝐁𝐄 𝐀 𝐃𝐈𝐒𝐀𝐒𝐓𝐄𝐑?
According to Newton’s First Law, an object in motion stays in motion unless acted upon by an external force.
So if Earth’s surface were to suddenly stop rotating, everything not rigidly attached to it- the oceans, the atmosphere, buildings, animals, and people- would keep moving at full speed (up to 1670 km/h at the equator).

That’s not just fast. It’s catastrophic.

What Would Happen Instantly
1. Massive Destruction
Every object on Earth would be hurled eastward at hundreds of meters per second.
A person weighing 70 kilograms would still be moving at 465 meters per second.
That gives a kinetic energy of about 7.6 million joules — the equivalent of 2 kilograms of TNT, per person. Imagine that on a global scale.
2. Supersonic Winds
The atmosphere wouldn’t stop just because the ground did. Air would keep moving, generating winds faster than the speed of sound- strong enough to flatten cities and strip landscapes bare.
3. Tsunamis on a Global Scale
The oceans would surge violently, forming tsunamis kilometers high that would devastate coastal regions. The water’s inertia would carry it far inland.
4. Global Earthquakes
The sudden change in rotational force would likely cause the Earth’s crust to shear and slip. The result would be global earthquakes and volcanic eruptions as tectonic stresses are suddenly released.

𝐖𝐇𝐀𝐓 𝐈𝐅 𝐈𝐓 𝐒𝐓𝐀𝐑𝐓𝐄𝐃 𝐑𝐎𝐓𝐀𝐓𝐈𝐍𝐆 𝐀𝐆𝐀𝐈𝐍 𝐀𝐅𝐓𝐄𝐑 𝟓 𝐒𝐄𝐂𝐎𝐍𝐃𝐒?
The Earth restarting its rotation just as suddenly would unleash a second wave of destruction.
The surface would begin moving again, but the atmosphere and oceans would still be out of sync, leading to yet another round of:
• Devastating winds
• Violent ocean surges
• Further structural destruction

𝐂𝐎𝐔𝐋𝐃 𝐓𝐇𝐈𝐒 𝐄𝐕𝐄𝐍 𝐇𝐀𝐏𝐏𝐄𝐍?
Short answer; no.
This is physically impossible with any known force. The Earth’s rotational kinetic energy is about 2.6 x 10^29 joules. That’s over 60,000 times more energy than was released by the asteroid that killed the dinosaurs.

To stop Earth in 5 seconds would require applying an unimaginably large torque, which would violate the conservation of angular momentum.

𝐒𝐔𝐌𝐌𝐀𝐑𝐘
A five-second pause in Earth’s rotation would not feel like five seconds- it would be the end of civilization as we know it.
Everything we take for granted- the oceans, the atmosphere, even the continents- is in delicate balance, moving smoothly with the planet’s rotation.𝐥

ɪꜰ ʏᴏᴜ ꜰɪɴᴅ ᴏᴜʀ ᴘᴏꜱᴛꜱ ɪɴᴛᴇʀᴇꜱᴛɪɴɢ, ᴘʟᴇᴀꜱᴇ ᴄᴏɴꜱɪᴅᴇʀ ᴛᴏ ꜰᴏʟʟᴏᴡ ᴛʜɪꜱ ᴘᴀɢᴇ.

ʙᴇꜱᴛ ᴡɪꜱʜᴇꜱ
Sondre Sundrønning

Picture is generated with AI