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A pickle jar can function as a tiny jet engine. The setup is simple: a glass jar with a small hole in the lid holds a volatile fuel like methanol, which evaporates to create a fuel and air mixture inside. A flame brought to the hole ignites it, and... the cycle begins. Here is what happens in each pulse. Combustion sends a sharp pressure spike through the jar, forcing hot gas out the lid hole as thrust. The escaping gas creates a brief partial vacuum inside, which pulls fresh air back in through the same hole. Residual heat ignites the new mixture automatically, and the cycle repeats dozens to hundreds of times per second. The jar and hole act as a resonant cavity, which is why it pulses instead of burning steadily. A single opening cannot handle exhaust and intake at the same time, so the system locks into a natural rhythm. It produces almost no real thrust, but it is a clear window into how actual pulsejet engines work, and the physics on display are the same ones used in real aerospace propulsion. Follow for more!show more

Mechanical Knowledge

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131,156 次观看 • 3 个月前 •via X (Twitter)

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A spark plug is a small device in a car’s engine that creates a tiny electric spark to ignite the fuel and air mixture inside the cylinder. This spark is what makes the engine start and keep running. Without spark plugs, gasoline engines wouldn’t work

A spark plug is a small device in a car’s engine that creates a tiny electric spark to ignite the fuel and air mixture inside the cylinder. This spark is what makes the engine start and keep running. Without spark plugs, gasoline engines wouldn’t work

HOW THINGS WORK

42,308 次观看 • 10 个月前

Forget matches; this is how our ancestors used the laws of thermodynamics to start fires in seconds using nothing but wood and air. The secret lies in the sudden increase in pressure. By trapping air in a narrow tube and forcing a piston down, you are doing work on the gas. In a closed system like this, that work translates directly into thermal energy. Because the movement is so fast, it is considered "adiabatic," meaning no heat escapes. The resulting flash of heat is intense enough to create a glowing ember, which is then transferred to a larger "tinder bundle" and blown into a flame.

Forget matches; this is how our ancestors used the laws of thermodynamics to start fires in seconds using nothing but wood and air. The secret lies in the sudden increase in pressure. By trapping air in a narrow tube and forcing a piston down, you are doing work on the gas. In a closed system like this, that work translates directly into thermal energy. Because the movement is so fast, it is considered "adiabatic," meaning no heat escapes. The resulting flash of heat is intense enough to create a glowing ember, which is then transferred to a larger "tinder bundle" and blown into a flame.

Mathematica

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The F-16’s afterburner boosts thrust by injecting additional fuel into the exhaust stream after the gases have already passed through the turbine. This creates a second stage of combustion that dramatically increases engine power. In normal operation, the engine compresses incoming air, burns it in the main combustion chamber, and uses the resulting energy to drive the turbine. The hot, high-speed exhaust then flows into the afterburner section, which contains flame holders—metal structures designed to stabilize the flame in the fast-moving airflow. When the pilot engages the afterburner, fuel is sprayed into this exhaust stream and ignites almost instantly. Because the exhaust still contains unused oxygen, the added fuel burns intensely, causing the gases to expand and exit the nozzle at much higher velocity. To maintain smooth airflow and prevent excessive pressure buildup, a variable-area nozzle opens wider. The outcome is a massive thrust increase—often 50% or more—accompanied by the bright, fiery plume that appears when the afterburner is active. 🔥✈️ 📸 by ig/fighteraircraft

The F-16’s afterburner boosts thrust by injecting additional fuel into the exhaust stream after the gases have already passed through the turbine. This creates a second stage of combustion that dramatically increases engine power. In normal operation, the engine compresses incoming air, burns it in the main combustion chamber, and uses the resulting energy to drive the turbine. The hot, high-speed exhaust then flows into the afterburner section, which contains flame holders—metal structures designed to stabilize the flame in the fast-moving airflow. When the pilot engages the afterburner, fuel is sprayed into this exhaust stream and ignites almost instantly. Because the exhaust still contains unused oxygen, the added fuel burns intensely, causing the gases to expand and exit the nozzle at much higher velocity. To maintain smooth airflow and prevent excessive pressure buildup, a variable-area nozzle opens wider. The outcome is a massive thrust increase—often 50% or more—accompanied by the bright, fiery plume that appears when the afterburner is active. 🔥✈️ 📸 by ig/fighteraircraft

aircraftmaintenancengineer

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The SR-71 Blackbird converts supersonic air to subsonic speeds using a movable, conical "spike" in the engine inlet that generates a series of shock waves, slowing air from over Mach 3 to roughly Mach 0.4 before it reaches the compressor. This process, crucial for the J58 engine, transforms high-speed, low-pressure air into high-pressure air at a manageable speed, generating a majority of the total thrust. Mechanism for Slowing Air •Inlet Spike Position: The sharp, cone-shaped spike moves up to 26 inches backward as the aircraft accelerates, optimizing shock wave alignment. •Oblique Shock Waves: At supersonic speeds, the spike produces a series of angled oblique shock waves that slow and compress the air. •Normal Shock Wave: A terminal shock wave forms at the inlet mouth, effectively slowing the air to subsonic velocity. •Variable Geometry: The inlet computer automatically manages the spike position and bypass doors to prevent "inlet unstart"—an immediate loss of thrust caused by shock wave misalignment. Benefits and Components •Pressure Conversion: The inlet acts like a "garden hose in reverse," where the reduction in speed is converted into massive pressure increase. •Subsonic Compression: The engine itself is a turbojet, which can only function on subsonic air. •Bypass Air: Excess air is bled off and reintroduced at the exhaust, adding more efficiency and thrust. •YouTube : How the Lockheed SR-71 Blackbird works by Amimagraffs

The SR-71 Blackbird converts supersonic air to subsonic speeds using a movable, conical "spike" in the engine inlet that generates a series of shock waves, slowing air from over Mach 3 to roughly Mach 0.4 before it reaches the compressor. This process, crucial for the J58 engine, transforms high-speed, low-pressure air into high-pressure air at a manageable speed, generating a majority of the total thrust. Mechanism for Slowing Air •Inlet Spike Position: The sharp, cone-shaped spike moves up to 26 inches backward as the aircraft accelerates, optimizing shock wave alignment. •Oblique Shock Waves: At supersonic speeds, the spike produces a series of angled oblique shock waves that slow and compress the air. •Normal Shock Wave: A terminal shock wave forms at the inlet mouth, effectively slowing the air to subsonic velocity. •Variable Geometry: The inlet computer automatically manages the spike position and bypass doors to prevent "inlet unstart"—an immediate loss of thrust caused by shock wave misalignment. Benefits and Components •Pressure Conversion: The inlet acts like a "garden hose in reverse," where the reduction in speed is converted into massive pressure increase. •Subsonic Compression: The engine itself is a turbojet, which can only function on subsonic air. •Bypass Air: Excess air is bled off and reintroduced at the exhaust, adding more efficiency and thrust. •YouTube : How the Lockheed SR-71 Blackbird works by Amimagraffs

Habubrats SR-71

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White Hole - A Black Hole With Time Reversed A White Hole is the time-reversed shadow of a Black Hole. It appears in the maximally extended Schwarzschild solution of General Relativity. The exterior geometry is the same ds² = −(1 − 2M/r)dt² + (1 − 2M/r)⁻¹dr² + r²dΩ² The difference is causal. A Black Hole lets paths enter but not escape. A White Hole lets paths emerge but not enter. No White Hole has been observed. But inside the equations of GR, the question is real: What does a Black Hole look like when time runs the other way?

White Hole - A Black Hole With Time Reversed A White Hole is the time-reversed shadow of a Black Hole. It appears in the maximally extended Schwarzschild solution of General Relativity. The exterior geometry is the same ds² = −(1 − 2M/r)dt² + (1 − 2M/r)⁻¹dr² + r²dΩ² The difference is causal. A Black Hole lets paths enter but not escape. A White Hole lets paths emerge but not enter. No White Hole has been observed. But inside the equations of GR, the question is real: What does a Black Hole look like when time runs the other way?

Mathelirium

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Hyundai Rotem has released a video introducing the LRAAM missile. It is currently being jointly developed with LIG Nex1. The integrated ducted ramjet propulsion is shown briefly. ●The difference from the initially revealed LRAAM is the addition of strakes. ●Since South Korea's numerous air-launched strike missile programs are considered first and the existence of the MBDA Meteor, the development period is generous and is scheduled to end in 2032. ●The consortium is competing with Hanwha Aerospace. ●The SRAAM short-range air-to-air missile is being developed by LIG Nex1. ●The solid fuel gas generator generates fuel-rich gas through primary combustion. Air entering through the air intake is mixed with the fuel-rich gas and then combusted a second time in the combustor to generate thrust. ●Ducted ramjet or ducted rocket propulsion systems simplify the fuel supply system and are lighter than liquid-fuel ramjet propulsion systems. Liquid-fueled ramjets offer better fuel efficiency and fuel supply control. However, they require additional fuel handling and are more expensive and heavier. ●As part of the recent success of its ground-launched hypersonic cruise vehicle, Hyundai Rotem also released CG of an air-launched hypersonic anti-ship cruise missile. The disclosed information mentions the use of hypersonic cruise missiles on land, sea, and air, and Hyundai Rotem is considered to be leading the way in cutting-edge engine and materials technology. ADD and Hanwha Aerospace are also participating in this sensitive program.

Hyundai Rotem has released a video introducing the LRAAM missile. It is currently being jointly developed with LIG Nex1. The integrated ducted ramjet propulsion is shown briefly. ●The difference from the initially revealed LRAAM is the addition of strakes. ●Since South Korea's numerous air-launched strike missile programs are considered first and the existence of the MBDA Meteor, the development period is generous and is scheduled to end in 2032. ●The consortium is competing with Hanwha Aerospace. ●The SRAAM short-range air-to-air missile is being developed by LIG Nex1. ●The solid fuel gas generator generates fuel-rich gas through primary combustion. Air entering through the air intake is mixed with the fuel-rich gas and then combusted a second time in the combustor to generate thrust. ●Ducted ramjet or ducted rocket propulsion systems simplify the fuel supply system and are lighter than liquid-fuel ramjet propulsion systems. Liquid-fueled ramjets offer better fuel efficiency and fuel supply control. However, they require additional fuel handling and are more expensive and heavier. ●As part of the recent success of its ground-launched hypersonic cruise vehicle, Hyundai Rotem also released CG of an air-launched hypersonic anti-ship cruise missile. The disclosed information mentions the use of hypersonic cruise missiles on land, sea, and air, and Hyundai Rotem is considered to be leading the way in cutting-edge engine and materials technology. ADD and Hanwha Aerospace are also participating in this sensitive program.

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A laser can ride a falling stream of water. Shine it through a hole in a milk-clouded soda bottle and the beam stays trapped by total internal reflection, the same physics as fiber optics, just liquid and gravity doing the guiding.

A laser can ride a falling stream of water. Shine it through a hole in a milk-clouded soda bottle and the beam stays trapped by total internal reflection, the same physics as fiber optics, just liquid and gravity doing the guiding.

Bluntly Put Philosopher (BPP)

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In offshore operations, excess gas cannot be released into the air, whilst pressure buildup inside pipelines is extremely dangerous. A flare gun fires a burning charge toward the flare stack. The gas ignites at a controlled point.

In offshore operations, excess gas cannot be released into the air, whilst pressure buildup inside pipelines is extremely dangerous. A flare gun fires a burning charge toward the flare stack. The gas ignites at a controlled point.

HOW THINGS WORK

840,057 次观看 • 2 个月前

Done and dusted. The secret? There is another hole on the container which he's using his thumb to block. As soon as he lifts his thumb away from the hole, air enters through the hole and the water starts dripping. The side hole is the “air door.” Air rushes in through that little side hole, and water happily runs out the bottom holes. For every drop that leaves the bottom, air has to sneak in somewhere to take its place.

Done and dusted. The secret? There is another hole on the container which he's using his thumb to block. As soon as he lifts his thumb away from the hole, air enters through the hole and the water starts dripping. The side hole is the “air door.” Air rushes in through that little side hole, and water happily runs out the bottom holes. For every drop that leaves the bottom, air has to sneak in somewhere to take its place.

Arojinle

389,064 次观看 • 4 个月前

James Sample: In the state of Georgia, there was a count, a recount, and there was a re-recount. All of the challenges that led to those counts in Georgia in 2020, is now the basis on which the affidavit for the warrant that was used to raid the Fulton County Election Office and seize those election materials. It is the same exact individuals, it is the same exact argument, and it is the same exact "evidence" that's being used, all of which was disproven time and again.

James Sample: In the state of Georgia, there was a count, a recount, and there was a re-recount. All of the challenges that led to those counts in Georgia in 2020, is now the basis on which the affidavit for the warrant that was used to raid the Fulton County Election Office and seize those election materials. It is the same exact individuals, it is the same exact argument, and it is the same exact "evidence" that's being used, all of which was disproven time and again.

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I love the Clone Wars so much because it'll have a scene where Jar Jar is doing dumb shit at a dinner party and then immediately follow it up with one of the hardest last stand scenes in the franchise

I love the Clone Wars so much because it'll have a scene where Jar Jar is doing dumb shit at a dinner party and then immediately follow it up with one of the hardest last stand scenes in the franchise

MA5K CEO

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Hole in one with a putter!!! A friend sent me this. A hole in one on the very first hole of a Pebble Beach trip! Hole 1 on The Hay course, designed by Tiger Woods. This is so awesome. And yes it counts as a Hole in Hole. Only haters would say otherwise.

Hole in one with a putter!!! A friend sent me this. A hole in one on the very first hole of a Pebble Beach trip! Hole 1 on The Hay course, designed by Tiger Woods. This is so awesome. And yes it counts as a Hole in Hole. Only haters would say otherwise.

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677,891 次观看 • 1 年前

The Elusive Concept of Time - Part II Pulsar Timing The first scene showed you Time as a local rate...clocks nearer the hole run slower, light gets redshifted, and spin drags the geometry around. This follow-up keeps the same idea, but turns it into a timing experiment. Instead of watching a clock face, we watch a receiver compare what arrives versus what flat space would predict. In the animation, the three small orange dots are the pulsars...orbiting emitters that flash regularly (in their own proper time). The larger white dot is the receiver sitting off to the side, and the little dark nub next to it is a tiny craft/antenna marker to make it feel like an instrument, not a star. When a pulsar lines up behind the hole relative to the receiver, the arrival times jump, because curved spacetime added extra delay and bent the path. #Physics #GeneralRelativity #PulsarTiming #BlackHoles #FrameDragging #Spacetime #Astrophysics #Time

The Elusive Concept of Time - Part II Pulsar Timing The first scene showed you Time as a local rate...clocks nearer the hole run slower, light gets redshifted, and spin drags the geometry around. This follow-up keeps the same idea, but turns it into a timing experiment. Instead of watching a clock face, we watch a receiver compare what arrives versus what flat space would predict. In the animation, the three small orange dots are the pulsars...orbiting emitters that flash regularly (in their own proper time). The larger white dot is the receiver sitting off to the side, and the little dark nub next to it is a tiny craft/antenna marker to make it feel like an instrument, not a star. When a pulsar lines up behind the hole relative to the receiver, the arrival times jump, because curved spacetime added extra delay and bent the path. #Physics #GeneralRelativity #PulsarTiming #BlackHoles #FrameDragging #Spacetime #Astrophysics #Time

Mathelirium

55,826 次观看 • 4 个月前

35 years ago, the New York Times warned of "a gaping hole" in the ozone layer, a potential "global crisis," they said. But looking at the latest data, the ozone hole today is the same size it was in the early 1990s and has been fluctuating within the same 20 to 30 million km2 band all that time. The only thing that changed was the media's coverage. It dropped the ozone scare and moved on to "climate doom" instead. Different crisis. Same playbook.

35 years ago, the New York Times warned of "a gaping hole" in the ozone layer, a potential "global crisis," they said. But looking at the latest data, the ozone hole today is the same size it was in the early 1990s and has been fluctuating within the same 20 to 30 million km2 band all that time. The only thing that changed was the media's coverage. It dropped the ozone scare and moved on to "climate doom" instead. Different crisis. Same playbook.

Electroverse

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🚨NEW: Joe Rogan: "I think it gets to a certain point with the pressure and the chaos and being the president and all the madness of the cameras in your face — the magnitude of it all wears on people, which is why they get so OLD." "The only one who's ever handled it is TRUMP. Trump looks younger!" "He's a freak. He's a genuine freak. Like, there's no one like that guy — which is the only reason why he survived all the sh*t they tried to put him through. It's the same reason why he can go through being president and it doesn't freak him out."

🚨NEW: Joe Rogan: "I think it gets to a certain point with the pressure and the chaos and being the president and all the madness of the cameras in your face — the magnitude of it all wears on people, which is why they get so OLD." "The only one who's ever handled it is TRUMP. Trump looks younger!" "He's a freak. He's a genuine freak. Like, there's no one like that guy — which is the only reason why he survived all the sh*t they tried to put him through. It's the same reason why he can go through being president and it doesn't freak him out."

Jason Cohen 🇺🇸

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octopus unscrewing the lid of a jar from the inside 📹Enoshima Aquarium

octopus unscrewing the lid of a jar from the inside 📹Enoshima Aquarium

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6,548,830 次观看 • 2 年前

🌀🕳️🪐 Why is the wormhole in Interstellar a sphere instead of a flat circle? ⭕️🕳️🪐* Because a real wormhole wouldn't look like a hole in space. It would look like a sphere. In movies and cartoons, wormholes are often shown as flat portals - like a doorway. But in real physics, space isn't 2D. It's three-dimensional. So if a wormhole connects two distant points in space-time, its entrance would extend in all directions. That's why in Interstellar, the wormhole appears as a floating sphere. No matter which direction you approach it from... You're still entering the same tunnel through space-time. The filmmakers actually worked with physicist Kip Thorne to make the depiction as scientifically accurate as possible. So that strange sphere in the movie? It might be the most realistic wormhole ever shown on screen. Sometimes science fiction is closer to real science than we think.*

🌀🕳️🪐 Why is the wormhole in Interstellar a sphere instead of a flat circle? ⭕️🕳️🪐* Because a real wormhole wouldn't look like a hole in space. It would look like a sphere. In movies and cartoons, wormholes are often shown as flat portals - like a doorway. But in real physics, space isn't 2D. It's three-dimensional. So if a wormhole connects two distant points in space-time, its entrance would extend in all directions. That's why in Interstellar, the wormhole appears as a floating sphere. No matter which direction you approach it from... You're still entering the same tunnel through space-time. The filmmakers actually worked with physicist Kip Thorne to make the depiction as scientifically accurate as possible. So that strange sphere in the movie? It might be the most realistic wormhole ever shown on screen. Sometimes science fiction is closer to real science than we think.*

DailyFacts 🕸️

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