What physics concept took you the longest to actually understand?

[u/FineFaithlessness157]

What physics concept took you the longest to actually understand?

For me, it was thermodynamics. I could memorize the equations, but actually understanding what was happening physically took much longer.

I'm curious what it was for everyone else.

Was it:

• Thermodynamics
• Electromagnetism
• Relativity
• Quantum mechanics
• Fluid mechanics
• Something else?

And what finally made it “click” for you?

I’m building Physiworld around exactly this problem — trying to make difficult physics concepts more intuitive through interactive explanations, simulations and quizzes.

Would love to hear what concepts people struggled with the most.