What If
An armor workshop with a power bill
Iron Man's Suit
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What If
What If
A grapnel is only as strong as its anchor
Batman's Grapnel
What If
Armor does not repeal inertia
The Batmobile
What If
A cape needs a real wing budget
Batman's Gliding Cape
What If
The web catches energy as well as a hero
Spider-Man's Web-Shooters
What If
Four arms still need a support polygon
Doctor Octopus's Arms
What If
Where can a kinetic suit put an impact’s energy?
Black Panther's Kinetic Suit
What If
Can a shield bounce back without losing momentum?
Captain America's Shield
What If
What pushes back when a hammer returns?
Thor's Returning Hammer
What If
Would a tiny hero still weigh as much?
Ant-Man's Suit
What If
What must the Speed Force supply or prevent?
The Flash at Full Speed
What If
Could sunlight power a superhero feat?
Superman's Solar-Powered Body
What If
Does a glowing bridge still need structure?
Green Lantern's Power Ring
What If
Can a portal give you free energy?
Doctor Strange's Portals
What If
Would Magneto attract every metal?
Magneto's Magnetic Workshop
What If
What would Storm have to move?
Storm's Weather Engine
What If
What would a healing factor consume?
Wolverine's Healing Factor
What If
What receives a repulsor’s opposite momentum?
Iron Man's Repulsor Flight
What If
Where does a cold ray put the heat?
Mr. Freeze's Cold Ray
What If
Hover and forward flight share a thrust budget
The Batwing
Mechanics
Mechanics
Why does distance change everything?
Levers & fulcrums
Mechanics
How do gears trade speed for strength?
Gears in motion
Mechanics
Why doesn’t a spinning wheel fall?
The surprising gyroscope
Mechanics
Can a rope make a load feel lighter?
Pulling with pulleys
Mechanics
What sets the rhythm of a swing?
A pendulum clock
Mechanics
Why does a spring stretch farther under a heavier load?
Spring force
Mechanics
How does a ramp trade distance for effort?
Loading ramp
Mechanics
How can a screw lift a heavy load?
Screw jack
Mechanics
Where does a hydraulic press get its extra force?
Hydraulic press
Mechanics
Why can a spinning rim keep a machine moving?
Flywheel storage
Mechanics
How does a cam turn rotation into a precise lift?
Cam and follower
Mechanics
Why does a ratchet turn in only one direction?
Ratchet hold
Mechanics
Why is a collapsed scissor lift harder to raise?
Scissor platform
Mechanics
Why put rolling balls between a shaft and its housing?
Rolling bearing
Mechanics
How can spinning balls close a throttle?
Flyball governor
Mechanics
Can sliding weights make a wheel power itself?
The overbalance wheel
Mechanics
How does a pendulum divide time into equal beats?
A seconds pendulum clock
Mechanics
How can a four-legged robot stay supported while a foot lifts?
Three feet on the ground
Mechanics
Why discard a spent booster before burning the upper stage?
Leave the spent booster behind
Mechanics
How can gears reproduce the slower year of Mars?
Gear a Martian year
Mechanics
Why can two arriving balls send two balls away?
Two balls in, two balls out
Mechanics
How can a laser join plastics through a clear cover?
Join through a clear plastic cover
Mechanics
What changes when a supercharger packs more air into a V8?
Eight cylinders and a blower
Mechanics
How do two threads become a lockstitch?
Two-thread lockstitch machine
Transport
Transport
Where will the shot land?
The field cannon
Transport
What keeps an airplane in the air?
How an airplane flies
Transport
How does a piston turn a wheel?
Inside a piston engine
Transport
How does a hand stop a bicycle?
How bicycle brakes stop a wheel
Transport
How can a heavy hull float and sink?
How a submarine dives
Transport
What does a bicycle gear change trade?
Bicycle drivetrain
Transport
How can two driven wheels turn at different speeds?
Car differential
Transport
How does a steering wheel move road wheels?
Rack steering
Transport
How does ABS keep a heavily braked wheel turning?
ABS pressure control
Transport
Why does stopping over more distance reduce force?
Seat belt impulse
Transport
How can a sailboat make progress toward the wind?
Sail and keel
Transport
Why does heated air lift a balloon?
Hot air balloon
Transport
Where does a turbojet’s forward push come from?
Turbojet flow
Transport
How much power does hovering require at a minimum?
Helicopter hover
Transport
How can a rigid railway axle follow a curve?
Railway wheelset
Transport
How does a double-deck airliner keep its cabin pressurized?
A double-deck pressure cabin
Transport
How does a lay tower avoid over-bending a flexible pipe?
Lay pipe without a sharp bend
Transport
Why does an afterburner need a wider nozzle?
Afterburner thrust stand
Electricity
Electricity
What makes a light turn on?
A little electricity
Electricity
How does electricity become rotation?
How an electric motor turns
Electricity
How does rotation become electricity?
Making electricity by turning
Electricity
Where does a battery’s energy go?
Inside a rechargeable battery
Electricity
Can one coil change another coil’s voltage?
Trading voltage with coils
Electricity
Why does a small air gap make a magnetic crane stronger?
The electromagnetic crane
Electricity
How can a tiny control circuit switch a separate load?
Inside an isolated relay
Electricity
Why does charging take longer than a flash?
A capacitor flash
Electricity
How do four diodes keep AC output flowing one way?
Four diodes, one direction
Electricity
Why does an overload take time to trip a breaker?
The warming circuit breaker
Electricity
Why can a small leakage trip a device carrying a large load?
The current that did not return
Electricity
Why can a divider voltage fall when a load is connected?
A loaded voltage divider
Electricity
How does a moving belt build up a high voltage?
The charge-carrying belt
Electricity
Why does a pan heat without touching a hot burner?
Heat from eddy currents
Electricity
Why does water electrolysis make twice as much hydrogen?
Two gases from water
Electricity
What happens inside a mechanical keyboard switch?
Inside a tactile key switch
Electricity
Why does a particle detector need many concentric layers?
Inside a layered particle detector
Home systems
Home systems
Where does the water go?
Water through a house
Home systems
What makes a toilet stop refilling?
How a toilet flushes
Home systems
Where does the heat from a fridge go?
Where a fridge puts the heat
Home systems
Why can a heat pump deliver more heat than it uses?
Moving heat into a house
Home systems
Why is there another weight beside the lift?
Inside an elevator shaft
Home systems
How does a spinning drum remove water from clothes?
A balanced spin cycle
Home systems
Why does the spray arm rotate without its own motor?
The arm driven by its jets
Home systems
Why does a thermostat switch above and below the setpoint?
The room that switches its heat
Home systems
How does smoke send light to a detector outside the beam?
Light scattered by smoke
Home systems
What actually releases a fire sprinkler?
The local thermal sprinkler
Home systems
How does a float keep a basement pump from running dry?
The pump that watches water rise
Home systems
Where do hardness ions go inside a softener?
The resin that exchanges ions
Home systems
What creates pressure in an espresso machine?
Pressure through the coffee bed
Home systems
Can fresh air be warmed without mixing it with exhaust air?
Fresh air through warm plates
Home systems
Where does a monthly mortgage payment go?
Principal, interest and escrow
Home systems
How do four saka guru support a Joglo’s tall central roof?
Four columns under a Joglo roof
Home systems
Why does a wider footing lower ground pressure?
A spread footing
Home systems
How does a long wall distribute its load?
A continuous wall footing
Home systems
Why can a larger raft settle less under the same load?
A raft on compressible ground
Human body
Human body
What’s happening inside you?
Inside the human body
Human body
What pulls air into your lungs?
How we draw a breath
Human body
Where does food go after you swallow?
The journey of a meal
Human body
How does a nerve decide to send a signal?
How a nerve carries a signal
Human body
Why does an image become blurry?
How an eye focuses
Human body
How does one membrane separate a chord?
A cochlea that sorts pitch
Human body
Why does steady spinning feel different from starting?
The inner ear motion sensor
Human body
Why does light in one eye change both pupils?
Two pupils, one light
Human body
Why does filtered glucose usually return to blood?
Filter, then reclaim
Human body
Can two pulling muscles hold one elbow still?
An elbow pulled both ways
Human body
How does food cross a shared air passage?
The shared throat crossing
Human body
What makes a platelet plug durable?
A platelet plug gains a net
Human body
Why can sweat remain without cooling much?
Why wet skin needs dry air
Human body
How can living cells replace solid bone?
Bone is continuously rebuilt
Human body
How does a signal change a membrane’s transport?
The membrane admits glucose
Living nature
Living nature
What keeps a pond in balance?
The living pond
Living nature
How does a leaf make food from light?
How a leaf makes food
Living nature
Where does a pollen grain need to land?
A bee and a flower
Living nature
Which way should the energy arrow point?
Following energy through nature
Living nature
What makes a pile of scraps break down?
How scraps become compost
Living nature
How does one living pore trade gas for water?
The living leaf valve
Living nature
What pulls a continuous water column upward?
A water column under tension
Living nature
Why does a sideways root bend downward?
How a sideways root bends
Living nature
Can a seed swell without becoming a seedling?
A seed spends its reserve
Living nature
How does a fern load a microscopic catapult?
A fern’s microscopic catapult
Living nature
Where do root and fungus exchange resources?
A root trades with a fungus
Living nature
Why send blood against the water?
Water and blood pass opposite ways
Living nature
How quickly can a pluck reach a spider?
The web carries a vibration
Living nature
Why does the wing buy time for a crosswind?
The maple seed’s falling wing
Living nature
How does an insect deliver air without lung blood?
Air goes straight to insect cells
Water & Earth
Water & Earth
How many lives can a water drop have?
A drop around the Earth
Water & Earth
How does falling water power a city?
Electricity from a dam
Water & Earth
Why does a river bend keep changing?
How rivers shape a bend
Water & Earth
Why are there two tidal bulges?
Why the sea rises and falls
Water & Earth
What happens when a stuck fault slips?
How a fault releases energy
Water & Earth
When can chamber pressure overcome a rock seal?
Pressure beneath a sealed vent
Water & Earth
Why does a tsunami slow and grow toward shallow water?
A wave entering shallow water
Water & Earth
How can groundwater flow through a solid-looking aquifer?
Water through connected pores
Light & sound
Light & sound
Where does a lens form its image?
Bending light with lenses
Light & sound
What happens to sunlight inside a raindrop?
A rainbow inside a raindrop
Light & sound
Can a mirror send a beam around a corner?
Bouncing light around a corner
Light & sound
What does it take to catch a sharp image?
How a camera captures light
Light & sound
Do air particles travel from a speaker to your ear?
Seeing sound travel
Light & sound
How do two open slits change detection probability?
Two slits, one probability pattern
Light & sound
Why does rotating a second polarizer dim polarized light?
Project light onto a second axis
Light & sound
Which rays stay trapped inside a fiber’s core?
Trap a ray inside a glass core
Light & sound
Why does a telescope need two lenses?
Inside a refracting telescope
Light & sound
What turns ordinary light into laser light?
When light starts to lase
Light & sound
Why does an echo take twice the travel time?
Measuring an ultrasound echo
Light & sound
Does moving the speaker do the same as moving your ear?
Which motion changes the pitch?
Light & sound
Why can a small repeated force make a large motion?
Tuning a driven oscillator
Light & sound
Where does the back of a headphone driver push the air?
Open-back headphones
Space
Space
How can falling keep missing Earth?
Falling around a planet
Space
Why does the Moon seem to change shape?
Why the Moon changes shape
Space
Why isn’t there an eclipse every month?
Making Sun, Moon and Earth line up
Space
Why is winter here summer somewhere else?
Why seasons swap hemispheres
Space
What can a rocket push against in empty space?
How a rocket pushes through space
Space
How can a planet hide in starlight?
Finding a planet in starlight
Space
Why must docking be slow and aligned?
A gentle spacecraft docking
Space
How can a spacecraft turn without pushing space?
Turning with a reaction wheel
Space
Can sunlight push a spacecraft?
Sailing on sunlight
Space
Why does a pulsar seem to blink?
A pulsar's sweeping beam
Digital signals
Digital signals
How can switches make a decision?
Building decisions from gates
Digital signals
How can eight switches become a letter?
A message made of bits
Digital signals
How does a message find another way?
How messages find their way
Digital signals
How can anyone lock a message only you can open?
A lock anyone can close
Digital signals
How does a wave carry a message?
Sending a message on a wave
Digital signals
How can a small team coordinate dependent tasks?
An office for dependent tasks
Digital signals
How do comparisons become sorted order?
The compare-and-exchange machine
Digital signals
When does a shorter description help?
A tape that counts its runs
Digital signals
Can redundant bits repair a damaged message?
The seven-bit repair rack
Digital signals
Who turns a domain name into an address?
A directory with three referrals
Digital signals
Why exchange three messages before sending data?
Two latches agree to connect
Digital signals
Does a pipeline finish an instruction faster?
Five stations share the clock
Digital signals
Why can an index skip most records?
A key chooses one drawer
Digital signals
How can a flat image become editable?
One image, six editable layers
Digital signals
Why is the second request faster?
The Redis caching machine
Digital signals
What happens under the keys?
Inside the Sony CMD-J5
Digital signals
Why should a repeated signal leave the factory asleep?
Signal factory
177 experiments to explore. No account. Just curiosity.