FormuLab

Formula Finder

Know your values, but not the equation? Find a relationship that connects them.

01 What do you want to find?

02 What do you already know?

Select the values given in your problem. You don’t need to enter numbers.

Your matches

Choose your known values

Let’s find a starting point.

Choose what you know about force, and the matching relationships will appear here.

This trial covers a small set of common formulas. A match confirms that the required inputs are selected; the physical assumptions still need to fit your problem.

Choose a formula from the values you know

Start with the quantity your problem asks for, then select the values given. The finder shows which relationships can use those values and which inputs are still missing. A match is a starting point: read the formula lesson to confirm its assumptions, units, and sign convention before calculating.

Net force from mass and acceleration

For a constant-mass system in an inertial frame, Newton’s second law relates net force to mass and acceleration.

Read Newton’s second law

Voltage from current and resistance

For an ohmic component, choose voltage as the target and use its current and resistance as the known values.

Read Ohm’s law

Average velocity from displacement and time

Use signed displacement over elapsed time. If you know total distance instead, you are finding average speed.

Read average velocity