Enter mass, velocity, and radius to find the centripetal force keeping an object moving in a circle.
Centripetal Force Calculator
LiveThe formula
A 2 kg object moving at 10 m/s on a 5-meter-radius circular path: Fc = (2 x 100) / 5 = 40 newtons.
Step-by-step guide
- Enter the object's mass, velocity, and the radius of its circular path.
- Read the centripetal force required to maintain that circular motion.
Why circular motion requires constant inward force
An object moving in a circle is constantly accelerating, even at a perfectly constant speed - because acceleration includes any change in direction, not just speed. That constant change in direction requires a continuous inward-pointing force (the centripetal force), without which the object would simply fly off in a straight line, following Newton's first law. This is exactly what you feel as the sideways pull in a car taking a sharp turn - the car's tires provide the centripetal force keeping you moving in a curve rather than straight ahead.
Common mistakes
Frequently asked questions
What provides the centripetal force in real situations?
It depends on the situation - friction between tires and road for a turning car, tension in a string for a swung ball, or gravity itself for a satellite orbiting a planet. The formula calculates how much force is needed; the source of that force varies by context.
Why does a tighter turn (smaller radius) need more force?
Because radius is in the denominator of the formula - a smaller radius at the same mass and speed means dividing by a smaller number, which increases the required force, matching the everyday experience that sharp turns feel more forceful than gentle curves.
Is centrifugal force real?
It's real as a perceived effect within a rotating frame of reference (like feeling pushed outward in a spinning car), but it's not a true force in the standard sense - what you're actually feeling is your own body's inertia resisting the car's inward centripetal acceleration.
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