Physics

• Are there any massless particles?
• As light from a star spreads out and weakens, do gaps form between the photons?
• Can a fire have a shadow?
• Can air make shadows?
• Can gold be created from other elements?
• Can light bend around corners?
• Can momentum be hidden to human eyes like how kinetic energy can be hidden as heat?
• Can one bit of light bounce off another bit of light?
• Can radio antennas emit visible light?
• Can sound waves generate heat?
• Can the decay half-life of a radioactive material be changed?
• Can you go fast enough to get enough mass to become a black hole?
• Can you make a shock wave of light by breaking the light barrier just like supersonic airplanes break the sound barrier?
• Can you make a sunset in a cup of milk?
• Could electronic devices charge themselves without being plugged into an electricity source?
• Could scientists perfectly simulate the entire universe in a computer, down to the last atom?
• Do atoms ever actually touch each other?
• Do flames contain plasma?
• Does a source of electricity ever run out of electrons?
• Does an atom have a color?
• Does an electron in an atom move at all?
• Does the negative mass of antimatter mean that it's gravitationally repelled from stars?
• Does time go faster at the top of a building compared to the bottom?
• How bad would a person's injuries be if an elevator's cables snapped at the 100th floor so that the elevator fell to the bottom?
• How can a clear object be transparent and visible at the same time?
• How can a material at a certain temperature have all of its molecules at the same energy?
• How can an electron leap between atomic levels without passing through all the space in between?
• How can glass produce glare without reflecting light?
• How can it be so hard to drag rubber across smooth glass if friction is caused by surface roughness?
• How can radioactive decay just happen with nothing triggering it?
• How can we travel to the past?
• How did Archimedes use mirrors to burn up invaders' ships?
• How do airplanes fly upside down if it's the shape of the wings that make them fly?
• How do free energy machines work?
• How do levers create energy if the conservation of energy does not allow energy to be created?
• How do projectors project the color black?
• How do scientists cool objects to absolute zero?
• How do tractor beams work?
• How do you focus regular light to make it a laser beam?
• How do you make a one-photon-thick beam of light?
• How does a microwave oven heat up food even though it emits no thermal radiation?
• How does a penny left on the track derail a train?
• How does a photon accelerate to light speed so quickly?
• How does quantum theory allow a rock to turn suddenly into a duck?
• How does sound going slower in water make it hard to talk to someone underwater?
• How high does a building have to be for a penny dropped from the top to kill a person on the ground?
• How is a magnetic field just an electric field with relativity applied?
• How long can you use a cell phone before getting a brain tumor?
• If I hammered and flattened a penny enough, could I cover the entire earth with it?
• If I'm on an elevator that breaks loose and plummets down the shaft, can I avoid harm by jumping at the last second?
• Is it possible to create magnetic waves?
• Is light a particle or a wave?
• Is metal a good heat shield?
• Is the reason that nothing can go faster than light because we have not tried hard enough?
• Is there a difference between thermal radiation and infrared radiation?
• Is there any difference between antimatter, dark matter, dark energy, and degenerate matter?
• Light has no mass so it also has no energy according to Einstein, but how can sunlight warm the earth without energy?
• Since gravity is unlimited, can we use it as an infinite energy source?
• What are some other ways to save energy in a car besides turning off the air conditioner and rolling down the windows?
• What did Schrodinger's Cat experiment prove?
• What is the most stable nucleus?
• What is the shape of an electron?
• What is the speed of dark?
• What is the speed of electricity?
• What is the speed of gravity?
• What is the strongest magnetic field possible? Is there a limit?
• What keeps a bicycle balanced?
• What makes heat rise?
• What makes radioactive atoms get old so quickly and decay?
• What makes the light waves in laser light parallel?
• What psychological effect makes notes on a piano that are an octave apart sound the same?
• What stops a piece of paper from being folded more than seven times?
• What would happen if you drove your car close to the speed of light and turned on the headlights?
• When does a light beam have only a single frequency?
• When does light travel in a straight line?
• When I bump one end of a long metal bar, the other end instantaneously moves. Can I use this to send messages faster than light?
• When I sit by a campfire, how does its hot air heat me?
• When I step out of the shower, what makes the tile floor so much colder than the bathroom mat?
• Why are all metals magnetic?
• Why are sound waves invisible?
• Why are the microwaves in a microwave oven tuned to water?
• Why are there only six fundamental colors: red, orange, yellow, green, blue, and violet?
• Why can't flat lenses focus light?
• Why do diamonds last forever?
• Why do mirrors flip left to right and not up to down?
• Why do quantum effects only happen on the atomic scale?
• Why does a person with only one working eye have zero depth perception?
• Why does a rainbow contain a pure spread of spectral colors?
• Why does a rainbow exist only in a narrow band?
• Why does air friction affect a car's gas mileage?
• Why does lightning push electricity through air, but common batteries do not?
• Why does my room get dark when I turn the lights off even if my window is shut?
• Why does water make a shirt darker?
• Why doesn't light carry momentum?
• Why doesn't my laptop emit radiation?
• Why don't atoms collapse if they are mostly empty space?
• Why don't electrons in the atom enter the nucleus?
• Why don't I feel the miles of air above me that are crushing me down?
• Why don't scientists use fractal concepts more considering that fractals are everywhere?
• Why is a 12-volt household battery harmless, but the shock from a 12-volt car battery will kill you?
• Why is gravity not a real force?
• Why is light pure energy?
• Why is physics scale invariant?
• Why is the centrifugal force talked about so much if it's not real?
• Why is the lowest temperature called absolute zero if it's relative to the frame of reference?
• Why is the speed of light a random finite number?
• Why is time frozen from light's perspective?
• Why was color invented by humans?
• Why were electrons chosen to be negatively charged? Wouldn't it make more sense to call electrons positively charged because when they move they make electricity?
• Why will a delivery truck filled with birds sitting on its floor be heavier than a truck with the same birds flying around inside.