Mechanics
Centripetal force
The inward force needed to maintain a circular path at constant speed.
The Formula
F = m x v^2 / r
The inward force needed to maintain a circular path at constant speed.
| Symbol | Meaning | Unit | Notes |
|---|---|---|---|
| F | Centripetal force | newtons | Inward force in newtons. |
| m | Mass | kilograms | Mass of the moving object. |
| v | Speed | metres per second | Tangential speed along the path. |
| r | Radius | metres | Radius of the circular path. |
What Each Symbol Means
Fnewtons
Centripetal force
Inward force in newtons.
mkilograms
Mass
Mass of the moving object.
vmetres per second
Speed
Tangential speed along the path.
rmetres
Radius
Radius of the circular path.
See It Worked With Real Numbers
A formula on its own does not tell you which number goes where. The how to calculate a centripetal force page applies this equation to a concrete case, shows every intermediate step, and names the mistakes that produce a wrong answer even when the algebra is right.
Where This Formula Appears
This equation is the working core of How To Calculate A Centripetal Force, filed under Science. Every number the guide produces comes from substituting into this one line.