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"I am too slow" is too vague to fix. A problem takes two kinds of time: the time to decide what to do, and the time to do it. Each has a different cure, so the first job is to find out which one is eating your minutes.
Why am I so slow at solving physics problems?
Often it is one of three things. You do not recognise the type of problem, so you try one approach after another. You recognise it but your algebra, units or arithmetic drag. Or you stay stuck on one question far too long because you do not want to give up on it.
Research on experts helps here. In a 1980 paper in Science, Larkin, McDermott, Simon and Simon argued that expert knowledge is indexed by large numbers of patterns that, once recognised, guide the expert to the relevant knowledge in a fraction of a second. In other words, much of an expert's speed comes from recognising what a problem needs, not from writing faster.
Is it slow understanding or slow execution?
Use the two-clock test for one week. Do 10 problems from a chapter you have finished. For each one, note two times:
Plan time: from reading the question to writing the first equation you are confident in.
Work time: from that equation to the final answer with units.
Then read your log:
Plan time is long and work time is short: this is a recognition problem. You understand the physics but cannot tell quickly which idea a question needs.
Plan time is short and work time is long: this is an execution problem. Practise algebra, approximations and mental arithmetic. Our guide to calculating faster without a calculator covers that.
Both are long and you often abandon problems: go back to the concept before you add speed work.
If the plan never comes and you keep reaching for the solution, set a rule for how long to stay stuck on a problem before you look.
How do I build a library of standard methods?
In a 1981 study, Chi, Feltovich and Glaser used sorting tasks to compare how experts and novices categorise physics problems. Experts started from the physics principle needed, while novices went by the problem's literal features, such as the objects it mentions. That is the difference a method library trains.
A method card has three lines: the cue (what in the question tells you), the method, and the trap. For example:
Cue: a block on a rough incline, asked for acceleration.
Method: free-body diagram, axes along and perpendicular to the incline, so a = g(sin θ − μ cos θ) when the block slides down.
Trap: the normal force is mg cos θ, not mg.
Check it with numbers: with θ = 30°, μ = 0.2 and g = 10 m/s², a = 10(0.5 − 0.2 × 0.866) ≈ 3.3 m/s².
Write one card per standard situation in each chapter, in your own words, after solving two or three problems of that type. Grinding new problems alone is not enough to build these patterns. Sweller (1988) argued that conventional problem solving, where you keep working to close the gap between where you are and the goal, uses so much mental capacity that little is left for learning the pattern itself.
If you keep choosing the wrong method, the Fermi Problem Library has worked problems with a step-by-step solver that explains the reasoning rather than printing an answer, so you can compare its first move with yours. If a card keeps failing because the idea underneath is shaky, look it up in the Fermi Concept Library before you drill again.
How should I use timed sets to get faster?
Cards only help if you can pick the right one under pressure. Chapter-wise practice hides that, because you already know the method before you read the question. In a classroom experiment with 126 seventh-grade students over three months, Rohrer, Dedrick and Stershic found that mixed (interleaved) practice, where students had to choose a strategy from the problem itself, beat blocked practice on unannounced tests given 1 day or 30 days after a review session. That study was in maths, but choosing a method is the same skill you need in physics.
A simple routine:
Shuffle 8 to 10 problems from three or four finished chapters.
Give yourself a fixed time and keep the two-clock log going.
Skip any problem where no plan comes within your limit, mark it, and move on.
Afterwards, for every slow or skipped problem, write or fix the method card.
If you are still learning a chapter, leave the timer off for now. Our phase plan for timed and untimed practice explains when to switch.
Start tonight: pick 10 problems from your last finished chapter, time them with two clocks, and let the log tell you what to fix.
