SolveTap

Free Chrome extension Physics

Physics Problem Solver: every formula, every step

SolveTap's Physics Problem Solver is a free browser extension that reads a screenshot of a physics problem and solves it the way a good tutor would: it lists the knowns and unknowns, states the governing equation in symbols, substitutes with units, and explains why each step is valid — from kinematics and forces to energy, waves and DC circuits.

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Why physics problems feel harder than the math in them

Most physics homework doesn't fail on algebra. It fails one step earlier — choosing which principle applies. Is this a kinematics problem or an energy problem? Does momentum conservation hold here? Which direction should the friction force point? Once the setup is right, the math is usually short.

That's why the Physics Problem Solver never jumps straight to numbers. Every solution follows the same discipline you're taught in class: identify the knowns and unknowns, pick the governing equation and say why it applies, solve symbolically, then substitute values with their units. If the units don't come out right, the setup was wrong — and the solver says so.

Because it works from a screenshot, it also reads the parts of the problem that live in the figure: the angle of an incline, the arrangement of resistors in a circuit, the direction of a velocity vector. It restates the setup it extracted before solving, so a misread diagram never becomes a silently wrong answer.

What it covers

  • Kinematics 1D and 2D motion, projectile motion
  • Forces & Newton's laws Free bodies, friction, inclines, tension
  • Work & energy Conservation, power, springs
  • Momentum Collisions, impulse, conservation
  • Circular motion & rotation Centripetal force, torque, angular momentum
  • Waves & sound Frequency, wavelength, standing waves, Doppler
  • Electricity Coulomb's law, fields, DC circuits, power
  • Thermodynamics Heat, ideal gases, first law
  • Optics Reflection, refraction, lenses and mirrors

Setup first, numbers second

Worked examples

These are the kinds of explanations the Physics Problem Solver produces from a single screenshot.

Horizontal projectile from a cliff

Kinematics

A ball rolls off a 20 m high cliff with a horizontal speed of 12 m/s. How long is it in the air, and how far from the base does it land? (Use g = 9.8 m/s², ignore air resistance.)

  1. Split the motion. Horizontal and vertical motion are independent. Vertically the ball starts with vy0 = 0 and accelerates at g; horizontally it moves at a constant 12 m/s.
  2. Time from the vertical drop. h = ½gt² → t = √(2h/g) = √(2 × 20 / 9.8) = √4.08 ≈ 2.02 s.
  3. Range from the horizontal motion. x = vxt = 12 m/s × 2.02 s ≈ 24.2 m.
  4. Unit check. √(m ÷ m/s²) = s ✓ and m/s × s = m ✓.

Time of flight ≈ 2.0 s; landing distance ≈ 24 m from the base of the cliff.

Common mistake the solver flags: using the 12 m/s in the vertical equation. The launch is horizontal, so the initial vertical velocity is zero.

Block sliding down a rough incline

Newton's laws

A 4.0 kg block slides down a 30° incline with coefficient of kinetic friction μ = 0.20. Find its acceleration. (g = 9.8 m/s²)

  1. Set up axes along the incline. Down-slope component of gravity: mg sin θ. Normal force: N = mg cos θ (no acceleration perpendicular to the surface).
  2. Friction opposes the motion. The block slides down, so kinetic friction acts up the slope: f = μN = μmg cos θ.
  3. Apply Newton's second law along the slope. ma = mg sin θ − μmg cos θ, so a = g(sin θ − μ cos θ) — the mass cancels.
  4. Substitute. a = 9.8 × (0.500 − 0.20 × 0.866) = 9.8 × 0.327 ≈ 3.2 m/s².

a ≈ 3.2 m/s² down the incline (and it doesn't depend on the block's mass).

Common mistake the solver flags: using mg for the normal force. On an incline, N = mg cos θ — friction is smaller than it would be on flat ground.

Series–parallel resistor circuit

DC circuits

A 12 V battery is connected to a 4 Ω resistor in series with a parallel pair: 6 Ω and 3 Ω. Find the current through each resistor.

  1. Reduce the parallel pair. 1/Rp = 1/6 + 1/3 = 1/2, so Rp = 2 Ω.
  2. Total resistance and battery current. Rtotal = 4 + 2 = 6 Ω, so I = V/R = 12/6 = 2.0 A. This full 2.0 A flows through the 4 Ω series resistor.
  3. Voltage across the parallel section. Vp = I × Rp = 2.0 × 2 = 4.0 V (both parallel branches see this same voltage).
  4. Branch currents. I6Ω = 4.0/6 ≈ 0.67 A and I3Ω = 4.0/3 ≈ 1.33 A. Check: 0.67 + 1.33 = 2.0 A ✓ (Kirchhoff's current law).

4 Ω: 2.0 A · 6 Ω: ≈ 0.67 A · 3 Ω: ≈ 1.33 A.

Common mistake the solver flags: assuming the parallel resistors split the current equally. Current divides in inverse proportion to resistance — the smaller resistor carries more.

How it works for physics

  1. Capture the problem. Screenshot the full question including any figure — incline angles, circuit layouts and vector directions are part of the problem.
  2. Confirm the setup. The solver lists the knowns, unknowns and the principle it plans to use, so a misread value gets caught before it propagates.
  3. Follow the derivation. Equations appear in symbols first, then with numbers and units. Ask follow-ups like "solve this with energy conservation instead" to see another valid path.

The point isn't the final number — it's recognizing the problem type fast on the exam, where no solver is allowed. That's the approach we explain on our academic integrity page.

A pre-flight checklist for any physics problem

The same four questions the solver answers before computing are worth asking yourself on every problem, solver or not:

  • What's constant? Constant velocity means forces balance; constant acceleration unlocks the kinematics equations; no external forces means momentum is conserved. The word "constant" in a problem is usually the key to it.
  • Draw before you derive. A free-body diagram or circuit sketch takes twenty seconds and prevents the most expensive class of error — a sign or direction flipped at the start.
  • Solve in symbols first. Numbers substituted early hide algebra mistakes and rounding drift. An answer like a = g(sin θ − μ cos θ) can be sanity-checked (set μ = 0, set θ = 90°) before any arithmetic happens.
  • Check the units and the size. If a car's speed comes out at 400 m/s or an electron's mass in kilograms looks large, the setup — not the calculator — is where to look.

Solutions from the Physics Problem Solver follow this checklist visibly, so each worked problem doubles as practice in the routine examiners actually reward.

Physics questions

Physics Problem Solver FAQ

Which physics topics does the solver cover?

Kinematics, projectile motion, Newton's laws, friction and inclines, work and energy, momentum, circular motion and rotation, waves and sound, thermodynamics basics, electrostatics, DC circuits and optics — roughly high school through introductory college physics.

Does it show the formulas it uses?

Yes. Each solution starts by listing the knowns and unknowns, states the governing equation in symbols first, then substitutes numbers with units, so you can follow the algebra and reuse the method.

Can it handle problems with diagrams, like inclined planes or circuits?

Yes. Screenshot the whole problem including the figure. The solver reads free-body setups, incline angles and circuit diagrams, and restates what it sees before solving so you can verify the reading.

Does it check units?

Yes. Units are carried through each substitution and the final answer includes a unit sanity check, which is where many physics mistakes are caught.

Is the Physics Problem Solver free?

Yes. It installs free from the Chrome Web Store and works without an account or payment card.

Try it on tonight's physics set

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