Physics Sensei questions & answers
Why Can I Follow the Solution but Can’t Solve the Problem Myself?
You check the solution after getting stuck. Every step makes sense. You think, “Oh, of course.” Then you try the next problem, and you’re stuck in the same place again.
It’s confusing. If you understood every step, why can’t you come up with them?
If you can follow the solution but can’t solve the problem yourself, the solution isn’t lying to you. It’s just showing you the finished path, and hiding how anyone found it.
What’s really going on
A written solution is cleaned up. It goes straight from the givens to the answer, one neat step after another. It doesn’t show the wrong turns, the restarts, or the moment someone asked, “What do I need to find this?”
That last part is the key. People who solve problems well often think backward. They start from what’s being asked and ask, “What would give me this?” Then, “What would give me that?” until they reach things they know.
A solution is written forward. Solving often happens backward. Reading forward doesn’t train you to think backward.
Why reading more solutions makes it worse
Each solution you read adds to the feeling that you get it. But every one shows the same forward path, so the backward thinking never gets practiced.
And because solutions never show wrong turns, your first wrong turn feels like failure. In reality, it’s a normal part of solving.
Why it’s hard to change
Thinking backward is uncomfortable at first. It feels like solving the problem in the wrong order. And taking a wrong turn on your own feels much worse than reading a clean answer.
But wrong turns are part of the job. The skill is knowing what to do after one.
The fix: work backward from the unknown
Practice the thinking the solution hides: start at the question and work back to what you know.
Try this on three problems this week: the backward chain
- Write the unknown at the top of the page. Ask: What are they asking?
- Under it, write what would give you that unknown. For example: “To get the time, I need the acceleration and the distance.”
- For each new thing you need, ask the same question: What would give me this? Keep going down the page.
- Stop when every branch ends in something the problem gives you. Ask: What do I know? Circle those.
- Now solve it forward, from the circles back up to the top. If a branch got stuck, that’s a wrong turn. Cross it out and try another.
Your page will look messier than the solution. That’s what real solving looks like.
What changes
The backward chain feels slow the first few times. Soon it becomes a habit: you’ll read a problem and immediately ask, “What do I need to get that?”
Wrong turns stop feeling like failure. They become part of the plan, something you cross out and move past.
Solutions are written forward. Solving runs backward. Practice the backward part.
Practice problems built for this
On Physics Sensei, every problem is solved step by step, and the first step is always “What are they asking?”, where the backward chain begins. Each one asks you to try it first, then gives you one more like it, with new numbers. You find out right away exactly where you slipped.
Your next step: try the backward chain on your next homework problem before you read any solution. Then check a problem on Physics Sensei.
More questions about studying and grades? See them all here.
Raul, Physics Sensei
