Physics Formulas

Live lab formula desk with domain lanes, an expression strip, SI scratch-solve for one missing variable, and handoffs to deep calculators when they exist.

Educational STEM literacy only. Ideal formulas assume classroom conditions. Not engineering certification or lab safety advice. Confirm units and assumptions with your course.

By Ahmet C. Toplutaş·Site owner & editor · Science tools

Last updated May 21, 2026 · Reviewed May 21, 2026 · Planning estimates only - not tax, medical, or investment advice

Browse sheet vs deep solver

STEM homework often starts with “which formula?” before “which peel?” This page is a lab formula desk: domain lanes, an expression strip, a light SI scratch-solve, and a handoff to the calculator that owns that relation deeply.

Framing is desk vs deep, not a single twin ladder. It is not Ohm’s power twin by itself, not Newton’s g-multiple board alone, and not a proportion cross-product tool.

Decision framing: “Which relation fits the sentence, what does SI scratch say, and which deep board should I open next?”

Educational STEM literacy only. Not engineering certification, not lab safety guidance, and not a substitute for your course assumptions. See our disclaimers.

Domain lanes on the strip

Filter by mechanics, motion, matter, energy, or electric. Each card shows the expression in mono so F = m a does not hide behind a long title. Pick a card to load defaults with one field blank for scratch.

Lanes are a browse aid, not a taxonomy exam. A speed problem lives under Motion; density and pressure under Matter; kinetic energy and average power under Energy; Ohm under Electric. If you already know the symbol, leave the filter on All and scan the strip.

Open Matter, then Density. Scratch ρ from m and V, then follow the deep handoff for unit ladders and material context.

SI scratch pad

Enter two known SI values and leave exactly one blank. The desk fills the missing term. Unit systems, peels, and ladders live on dedicated boards when a handoff link appears.

Keep every field in the unit printed on the label (N, kg, m/s², Pa, Ω, and so on). Mixing grams with kilograms or minutes with seconds inside this pad will invent a wrong close. Convert first, then scratch.

Tip: blank the quantity the homework asks for. If the prompt says “find force,” leave F empty and fill m and a.

When the ideal formula lies

Friction and drag change net force. Semiconductors are not ohmic. Compressible fluids complicate density and pressure. Relativistic speeds break classical KE. If your problem states ideal conditions, the desk matches; otherwise treat the number as a first sketch.

Course wording matters. “Neglect friction,” “ideal resistor,” and “constant density” are permission to use these identities. Without that language, ask whether a deeper model (or a different tool) is required before you trust the scratch result.

Relations on the desk

Common classroom identities in SI. Rearrange by algebra: any one symbol can be the unknown when the other two are known (for three-term relations). Kinetic energy uses the square of speed, so solving for v takes a square root and returns a non-negative speed sketch.

F = m a v = d / t ρ = m / V P = F / A KE = ½ m v² P = W / t V = I R

Note the overloaded letter P: pressure (force over area) and power (work over time) share a symbol in many textbooks. The active expression strip tells you which board you are on.

Where this hands off

Deep boards for the relations that already have full v2 peels.

Newton's law (F = m a with weight twin)
Density (ρ = m / V)
Ohm's law (V = I R + power)
Speed / pressure
Glossary terms: science glossary

Worked scenarios

Scenario A: Newton scratch. Mass 2 kg, a = 5 m/s², blank F → 10 N. Handoff to the Newton board for weight vs net force and g-multiple peels.

Switch to Electric → Ohm's law. Blank V with I = 2 A and R = 6 Ω → 12 V, then open the deep Ohm board for power twin and decade load ladder.

Scenario B: Density. m = 2 kg, V = 0.002 m³ → ρ = 1000 kg/m³ (water-like sketch). Continue on the density calculator for specific gravity context.

Scenario C: Kinetic energy. m = 2 kg, v ≈ 15.81 m/s → KE ≈ 250 J. No deep board yet; scratch stays on the desk.

Scenario D: Pressure. Close P = F/A with F = 1000 N and A ≈ 0.00987 m² → about one atmosphere in Pa, then hand off for unit peels on the pressure calculator.

Scenario E: Average speed. d = 100 m, t = 5 s → v = 20 m/s. Open the speed calculator when you need unit conversions or pace-style framing.

Common mistakes

Leaving zero or two fields blank (scratch needs exactly one missing).
Mixing units inside the SI scratch pad.
Treating the desk as a full replacement for a deep sibling board.
Applying ideal Ohm or F = m a when the problem includes non-ideal effects.
Skipping the glossary when a symbol is unclear.

How to use this desk

Filter a domain lane or browse all formulas.
Select an expression card; confirm the mono formula strip.
Enter two SI knowns, blank one field, read the scratch result.
Follow the deep handoff when present. Share writes the formula id; typing does not rewrite the address bar.

When not to stop at the desk

Stop here to pick a relation and close a quick SI unknown. Hand off for deep peels, unit systems, or glossary definitions. For multi-step lab reports, follow your course method.

Density: density calculator.
Ohm's law: Ohm's law.
Newton's law: Newton's law.

Frequently asked questions

What is this physics formulas page?

It is a lab formula desk: pick a common relation by domain, read the expression, scratch-solve one missing SI variable, then hand off to a deeper calculator when one exists (density, Ohm’s law, Newton’s law, speed, pressure).

How does scratch-solve work?

Enter two known values in SI units and leave exactly one field blank. The desk fills the missing term for the active formula. It is homework literacy, not a full unit-converter suite.

Why hand off to other calculators?

Deep boards add peels, ladders, and unit systems. This page routes you to the right relation quickly; sibling tools go deeper on one equation.

Which formulas are included?

Newton’s second law F = m a, average speed v = d/t, density ρ = m/V, pressure P = F/A, kinetic energy KE = ½mv², average power P = W/t, and Ohm’s law V = I R.

Are these ideal formulas always true?

No. Friction, drag, non-ohmic devices, compressible fluids, and relativistic speeds break the ideal sketch. Treat results as classroom relations unless your problem states the same assumptions.

Is this engineering certification?

No. It is educational STEM literacy only. Safety-critical design needs standards, proper analysis, and professional review.

How is this different from the density or Ohm’s law calculators?

Those pages go deep on one relation. This desk is a multi-formula index with a light SI scratch pad and clear handoffs.

Sources

Loading…

Browse sheet vs deep solver

Framing is desk vs deep, not a single twin ladder. It is not Ohm’s power twin by itself, not Newton’s g-multiple board alone, and not a proportion cross-product tool.

Decision framing: “Which relation fits the sentence, what does SI scratch say, and which deep board should I open next?”

Educational STEM literacy only. Not engineering certification, not lab safety guidance, and not a substitute for your course assumptions. See our disclaimers.

Domain lanes on the strip

Open Matter, then Density. Scratch ρ from m and V, then follow the deep handoff for unit ladders and material context.

SI scratch pad

Enter two known SI values and leave exactly one blank. The desk fills the missing term. Unit systems, peels, and ladders live on dedicated boards when a handoff link appears.

Tip: blank the quantity the homework asks for. If the prompt says “find force,” leave F empty and fill m and a.

When the ideal formula lies

Relations on the desk

F = m a v = d / t ρ = m / V P = F / A KE = ½ m v² P = W / t V = I R

Note the overloaded letter P: pressure (force over area) and power (work over time) share a symbol in many textbooks. The active expression strip tells you which board you are on.

Worked scenarios

Scenario A: Newton scratch. Mass 2 kg, a = 5 m/s², blank F → 10 N. Handoff to the Newton board for weight vs net force and g-multiple peels.

Switch to Electric → Ohm's law. Blank V with I = 2 A and R = 6 Ω → 12 V, then open the deep Ohm board for power twin and decade load ladder.

Scenario B: Density. m = 2 kg, V = 0.002 m³ → ρ = 1000 kg/m³ (water-like sketch). Continue on the density calculator for specific gravity context.

Scenario C: Kinetic energy. m = 2 kg, v ≈ 15.81 m/s → KE ≈ 250 J. No deep board yet; scratch stays on the desk.

Scenario D: Pressure. Close P = F/A with F = 1000 N and A ≈ 0.00987 m² → about one atmosphere in Pa, then hand off for unit peels on the pressure calculator.

Scenario E: Average speed. d = 100 m, t = 5 s → v = 20 m/s. Open the speed calculator when you need unit conversions or pace-style framing.

Frequently asked questions

What is this physics formulas page?

How does scratch-solve work?

Enter two known values in SI units and leave exactly one field blank. The desk fills the missing term for the active formula. It is homework literacy, not a full unit-converter suite.

Why hand off to other calculators?

Deep boards add peels, ladders, and unit systems. This page routes you to the right relation quickly; sibling tools go deeper on one equation.

Which formulas are included?

Newton’s second law F = m a, average speed v = d/t, density ρ = m/V, pressure P = F/A, kinetic energy KE = ½mv², average power P = W/t, and Ohm’s law V = I R.

Are these ideal formulas always true?

No. Friction, drag, non-ohmic devices, compressible fluids, and relativistic speeds break the ideal sketch. Treat results as classroom relations unless your problem states the same assumptions.

Is this engineering certification?

No. It is educational STEM literacy only. Safety-critical design needs standards, proper analysis, and professional review.

How is this different from the density or Ohm’s law calculators?

Those pages go deep on one relation. This desk is a multi-formula index with a light SI scratch pad and clear handoffs.

Browse sheet vs deep solver

Domain lanes on the strip

SI scratch pad

When the ideal formula lies

Relations on the desk

Where this hands off

Worked scenarios

Common mistakes

How to use this desk

When not to stop at the desk

Frequently asked questions

What is this physics formulas page?

How does scratch-solve work?

Why hand off to other calculators?

Which formulas are included?

Are these ideal formulas always true?

Is this engineering certification?

How is this different from the density or Ohm’s law calculators?

Sources

Browse sheet vs deep solver

Domain lanes on the strip

SI scratch pad

When the ideal formula lies

Relations on the desk

Where this hands off

Worked scenarios

Common mistakes

How to use this desk

When not to stop at the desk

Frequently asked questions

What is this physics formulas page?

How does scratch-solve work?

Why hand off to other calculators?

Which formulas are included?

Are these ideal formulas always true?

Is this engineering certification?

How is this different from the density or Ohm’s law calculators?

Sources

What this number means

Share your calculation