Calculate centrifugal force (F = mω²r) from mass, radius, and rotational speed. Supports RPM, rad/s, and velocity inputs with G-force analysis.
Centrifugal force is the apparent outward force seen in a rotating reference frame. The force is a frame-dependent effect, but its consequences are very real in spinning systems such as centrifuges, washing machines, and rotating habitats.
This calculator uses mass, radius, and rotation speed to compute centrifugal force from RPM, angular velocity, or tangential velocity. It also reports centripetal acceleration, G-force, tangential speed, and rotation period so the motion can be read in more than one way.
Preset examples and the force-versus-RPM table help translate the math into familiar systems instead of leaving it as an abstract circular-motion formula.
Rotating systems often need force estimates in a form that is easy to compare against machine limits or comfort limits. Showing RPM, radius, and G-force together makes it simpler to see how quickly the load grows as speed rises.
F = mω²r = mv²/r. ω = 2π × RPM / 60. G-force = ω²r / 9.81. Tangential velocity v = ωr. Period T = 2π/ω.
Result: 19,739 N (402 G)
A 5 kg load of clothes in a washing machine spin cycle (1200 RPM, 0.25 m radius) experiences 19,739 N of centrifugal force — about 402 times its weight. This is what extracts water from the fabric.
Centrifugal force considerations are critical in designing rotating machinery: turbine blades experience enormous centrifugal loads at 10,000+ RPM, requiring superalloy materials. Centrifugal pumps use vane rotation to accelerate fluid outward, converting rotational energy to flow energy. Centrifugal clutches engage automatically above a set RPM.
In a rotating reference frame, two fictitious forces appear: centrifugal force (outward, proportional to radius) and Coriolis force (perpendicular to velocity). Both are important for weather systems on Earth and for objects moving within large rotating structures.
Ultracentrifuges spin at up to 150,000 RPM, achieving over 1,000,000 G. Uranium enrichment gas centrifuges operate at 50,000-70,000 RPM. At these speeds, molecular weight differences cause isotopic separation — UF₆ with U-238 moves slightly outward compared to UF₆ with U-235.
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In an inertial (non-rotating) frame, centrifugal force does not exist — only centripetal force is real. However, in the rotating reference frame, centrifugal force is a perfectly valid and useful concept for calculating apparent forces.
Centripetal force is the real inward force that keeps an object moving in a circle (like tension in a string). Centrifugal force is the apparent outward force felt by the object in the rotating frame. They have equal magnitude but opposite directions.
During the spin cycle, clothes are pushed outward against the drum at hundreds of G. Water, being less bound to the fabric, is flung through the drum holes, dramatically reducing drying time.
Yes — a rotating space station can simulate gravity on its outer wall. For 1G, you need ω²r = 9.81, which can be achieved with a 100 m radius spinning at about 3 RPM for acceptable comfort.
Centrifugal force depends on ω² (angular velocity squared). Since ω is proportional to RPM, doubling the RPM quadruples the force. This is why high-speed centrifuges achieve enormous G-forces.
Material strength limits RPM. The spinning object must withstand the centrifugal stress. This is why turbine blades, centrifuge rotors, and flywheels are made from high-strength materials.