Choose a formula, enter what you know, leave the unknown blank, and get a full explanation — just like your teacher would give you.
How to use: Fill in the values you know. Leave exactly one field blank — that is the value we will calculate and explain for you.
Your step-by-step solution will appear here once you click Solve. Each step is explained in plain English so you can follow along and understand the method.
These are the core formulas in the solver. Knowing what each variable represents is the first step to solving any numerical.
v = d ÷ t
v = speed, d = distance, t = time.
Speed tells you how much distance is covered every unit of time.
F = m × a
F = force (N), m = mass (kg), a =
acceleration (m/s²). This is Newton's Second Law of Motion.
W = F × d
Work is only done when a force
moves an object. If there's no movement, there's no work done —
even if you're pushing hard!
P = W ÷ t
Power is the rate of doing work. A
100 W bulb transfers 100 J of energy every single second.
P = F ÷ A
Same force over a smaller area →
higher pressure. That is why a knife cuts but a spoon does not.
V = I × R
V = voltage (V), I = current (A),
R = resistance (Ω). The foundation of all basic circuit problems.
KE = ½mv²
The energy an object has because
it is moving. Velocity is squared, so doubling speed quadruples
KE!
ρ = m ÷ V
Density tells you how much mass is
packed into a given volume. Lead is denser than wood — more mass,
same volume.
Many students panic when they see a physics numerical. The good news: every numerical follows the same process. Once you know the process, no formula can trip you up.
Before touching a formula, write down every piece of information the question gives you. Write the symbol and value next to each other. For example: d = 150 m, t = 30 s. This instantly shows you what you have and what you are missing.
The question always tells you what to find. Underline or circle it. Write it down as: Find: v = ? Now you know exactly which formula you need — the one that connects what you know to what you need to find.
Write the formula in full before substituting any numbers. This is a habit that earns marks even if you make a calculation error later. Examiners reward method marks.
Replace each symbol with its value. Keep the units next to every number. This helps you catch mistakes — if the units do not simplify correctly, something is wrong.
Do the arithmetic, round sensibly (2–3 significant figures is usually right), and write a clear final statement: "Speed = 5 m/s". An answer without units is an incomplete answer.
Golden rule: Always include the unit in your final answer. In O Level marking schemes, a missing unit often costs you a mark — even if your number is correct.