"Why is physics so hard" is typed by students in the first term of the course and by their parents after the first test, and the honest answer is that physics is not harder than other subjects in the amount you must learn, it is harder in the kind of thinking it asks for, and school rarely teaches that kind of thinking explicitly. This article gives the four real reasons, the three places in the course where most students fall, the five habits that fix it, and how a parent can tell the difference between a child who needs a term of the right habits and one who needs help now. We teach physics 1-on-1 from middle school to AP, A-Level and IB, and everything here is from that.
The four real reasons
1. Physics uses maths as a language, not as a skill. In maths class a student solves the equation. In physics the equation is a sentence about the world: F = ma says "the harder you push, the faster it speeds up, and heavier things speed up less". A student whose algebra is still a slow skill (rearranging, substituting, handling units) has no attention left for the sentence, and reads every problem as "which formula". This is the most common reason, and it is fixable in weeks, because the algebra needed is small: rearranging, ratios, right-angle trigonometry, and later a little calculus.
2. The ideas contradict everyday experience. Everyday life teaches that things stop unless you keep pushing (they do not; friction stops them), that heavier things fall faster (they do not), that a ball thrown upward has a force pushing it up while it rises (it does not; only gravity acts). Newton's first law is the first idea in school that a student must accept against their own intuition, and a student who has not made that switch will get forces wrong in every topic after it.
3. It is cumulative in a way other subjects are not. A gap in kinematics (velocity, acceleration, the graphs) reappears in forces, then in energy, then in momentum, then in circuits as the same reasoning with different quantities. A student who "did badly in the first unit but it's over now" carries that unit for the year. Biology forgives a bad unit; physics does not.
4. It is taught by formula when it should be taught by picture. The formula sheet is the problem. A student who sees v² = u² + 2as as the thing to find has been taught physics backwards. The good sequence is: draw the situation, mark what is known, decide what is happening physically, and only then pick the relationship that connects the known to the unknown. Most textbooks and many classrooms do the last step first.
Where students fall, in order
| Topic | Why students fall there | What it looks like |
|---|---|---|
| Kinematics (motion, graphs) | Confusing distance with displacement, speed with velocity, and the gradient of a graph with its height | Right answers to plug-in problems, wrong answers to graph problems |
| Forces and Newton's laws | The intuition switch; free-body diagrams drawn wrong or not at all | "There is a force pushing the ball up"; normal force missing; mass and weight swapped |
| Energy | Reasoning about a quantity you cannot see; choosing the system | Energy "lost"; kinetic and potential mixed up; work done by the wrong force |
| Momentum and collisions | Vectors: direction matters and signs are dropped | Right magnitudes, wrong signs |
| Circuits | Current is not "used up"; potential difference is abstract | Bulbs in series and parallel reasoned wrongly; V and I confused |
| Waves and optics | Diagrams again; ray diagrams and wavefronts | Memorised rules applied to the wrong situation |
| AP / A-Level: rotation, fields, induction | The abstraction doubles; calculus arrives | The strongest students' first real difficulty |
Forces is the wall for most. A student who can draw a correct free-body diagram for a box on a slope, a lift accelerating upward and a ball at the top of its flight has done the hardest thing in school physics.
The five habits that fix it
- Draw first. Every problem, a sketch with the quantities marked, before any equation. Free-body diagrams for forces; energy bar charts for energy; circuit diagrams redrawn cleanly. Thirty seconds that prevents half of all errors.
- Units, always. Write every number with its unit and carry the units through the algebra. A wrong unit at the end is a wrong method, caught for free. Convert to SI first (km/h to m/s, grams to kilograms).
- Algebra before numbers. Solve for the unknown in symbols, then substitute at the end. It is faster, it shows the method for the mark scheme, and it makes the physics visible: a formula for the time to fall that does not contain the mass says something.
- One type at a time. Do ten problems of one kind (constant acceleration, say) until they are automatic, then the next kind, and only then mixed sets. Mixed practice too early teaches guessing.
- Spaced revisiting. Ten minutes a week on last month's topics, because physics is cumulative. Two problems from each old unit, no notes. This is the habit that separates the A students, and almost nobody does it unprompted.
A student who does these five for one term moves about a grade, in our experience, and the change is in method, not ability.
How to tell if your child needs help now
| Sign | What it usually means | What to do |
|---|---|---|
| Right answers on homework, wrong on tests | Problems done with the formula sheet and the worked example open | Habit 4: closed-book problem sets by type |
| "I understand it in class but can't do the problems" | The picture step is missing; the class showed the equation | Habit 1 for a fortnight, with someone checking the diagrams |
| Algebra errors, sign errors, units missing | The maths is still a skill, not a language | Two weeks of rearranging and units practice, separate from the physics |
| Fine until forces, then a collapse | The intuition switch has not happened | Newton's laws taught again from scratch with experiments, not formulas; a tutor's job |
| Fine until AP or A-Level, then a collapse | The abstraction doubled and the habits were never built | The five habits, now, with past-paper questions |
The first three fix at home in a month with the habits above. The last two are where a 1-on-1 tutor earns the fee, because the fix is teaching the idea differently, not more practice of the same idea.
What we do
A 1-on-1 online class with a tutor who holds a master's in physics: the picture first, the habits built into every class, one problem type at a time, past papers and free-response questions marked to the real scheme from the first term of an exam course. Middle-school physical science, high-school physics, AP Physics 1, 2 and C, GCSE and IGCSE, A-Level and IB, in the school's order. The recording and notes after every class, the same tutor for the course, US$10 to $13 an hour (about £8 to £10, A$14 to A$19), billed monthly. The physics page has the courses; the free 30-minute class is a real lesson, usually on forces, because that is where the answer to "why is physics so hard" lives.
Questions parents ask
1Why is physics so hard for me?
2Is physics harder than chemistry or biology?
3What is the hardest topic in physics?
4How do I get better at physics?
See how we teach this, 1-on-1 online →
Shobha
Founder and lead tutor, Science with Shobha
Teaching maths, science and English to children online since 2018. 500+ students, 20+ tutors, families in nine countries.