What units should I use?

Keep a consistent SI set: kg, m, s, and N (kg·m/s²).

Is speed the same as velocity?

This worksheet returns a scalar speed or distance/time relation, not a vector velocity.

Can acceleration be zero when solving for mass?

No. Dividing by zero is rejected; a zero acceleration with nonzero force is inconsistent with F = ma.

Physics Force Calculator

Rearrange F = ma or constant-speed distance relations without hiding the formula you used.

Force / mass / acceleration

Speed / distance / time

Clear formula label

Solves F = m × a for force, mass, or acceleration, and v = d ÷ t for speed, distance, or time using SI-style units you enter.

Limitation: Educational formula worksheet only.

Jump to calculator · Sources & review

Solve forForce (N)Needed when solving for mass or acceleration.Mass (kg)Needed when solving for force or acceleration.Acceleration (m/s²)Needed when solving for force or mass.Speed (m/s)Needed when solving for distance or time.Distance (m)Needed when solving for speed or time.Time (s)Needed when solving for speed or distance.

How to Use the Physics Worksheet

Choose the unknown, fill the two knowns for that branch, and leave unused fields alone.

Select whether you are solving a force-law unknown or a constant-speed unknown.

Net force, not every force

In F = ma, F is the net force along the acceleration direction. Do not drop friction or other forces unless they truly cancel.

What Each Mode Returns

Force modes rearrange Newton’s second law. Speed modes rearrange the constant-speed definition v = d/t. They are separate branches—do not mix force inputs into a speed solve.

Physics Formula Examples

Force from mass and acceleration

Known values

solveFor:force

mass:10

acceleration:3

Unknown

30 N

F = 10 × 3 = 30 N.

Average speed on a path

Known values

solveFor:speed

distance:100

time:20

Unknown

5 m/s

v = 100 ÷ 20 = 5 m/s for constant-speed travel.

Name the branch

If you change Solve for, ignore leftover numbers from the other branch—they are not used.

Frequently Asked Questions

Only the two knowns for the selected unknown. Extra fields from the other branch are ignored.

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Force and Speed Formulas

Both branches are algebraic rearrangements of standard introductory physics relations.

Formula

F = m × a

Newton’s second law

F = m × a

Mass from force

m = F ÷ a

Acceleration from force

a = F ÷ m

Constant speed

v = d ÷ t

Scientific Background

Assumptions: SI-compatible units, constant mass, and—for the speed branch—constant speed (or average speed defined as total distance over total time). Limitations: vector directions, friction, variable acceleration, and relativistic corrections are out of scope.

Sources & review

Physics Force Calculator documents the references behind its formulas and assumptions. Always treat results as educational estimates, not personalized professional advice.

Last reviewed

July 22, 2026

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