Grades 9–12 · 8 connected explanations
Energy & Motion
Compare electrical and thermal energy conversion, then examine energy balance and gravity at planetary and stellar scales.
Materials & Matter
How do electrons and ions follow different routes in a discharging cell?
A discharging cell connects chemical processes with electrical charge routes.
Machines
How does an electric motor make a shaft turn?
An electric motor turns electromagnetic interactions into shaft rotation.
Machines
How does a heat engine turn heat into work?
A heat engine’s model makes both useful work and transferred heat explicit.
Systems
How does a hydrogen fuel cell make electricity without burning fuel?
A fuel cell provides another route from chemical processes to electrical output.
Earth & Space
How does the greenhouse effect fit an energy balance?
An energy-balance model links Earth’s incoming and outgoing radiation.
Earth & Space
Why does the Sun keep shining?
Nuclear fusion explains the Sun’s continuing energy supply on a different physical scale.
Systems
How can a spacecraft keep falling without reaching the ground?
Orbital motion connects gravitational acceleration with continual free fall.
Earth & Space
How can gravity make one distant galaxy look like a ring?
Gravitational lensing reveals another relationship between mass, geometry and light.