{"openapi":"3.1.0","info":{"title":"Circular Motion API","version":"1.0.0","description":"Uniform circular-motion physics as an API, computed locally and deterministically. The centripetal-force endpoint computes the centripetal acceleration a = v²/r = ω²·r — always pointing toward the centre — and the centripetal force F = m·a that holds a body on its circular path, from the mass, the radius and either the linear or the angular velocity, and reports the equivalent g-force. The angular endpoint converts between every way of describing rotation — angular velocity (rad/s), revolutions per minute, frequency, period and, given a radius, the linear (tangential) velocity — using ω = 2π·f = 2π/T = v/r. The centrifuge endpoint computes the relative centrifugal force (RCF, in g) of a centrifuge rotor from its speed in rpm and radius, RCF = ω²·r / g, or inverts it to give the rpm needed to reach a target RCF. Masses are in kg, radii in m (mm for the centrifuge), velocities in m/s, angular velocities in rad/s and forces in N. Everything is computed locally and deterministically, so it is instant and private. Ideal for physics-education, mechanical, automotive, lab-centrifuge and amusement-ride app developers, rotational-motion and g-force tools, and STEM teaching. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is uniform circular motion; for gravitational orbits use a gravitation API, for a vehicle on a banked curve a banked-curve API and for pendulum oscillation a pendulum API.","contact":{"name":"PremiumApi","url":"https://www.oanor.com/by/premiumapi"}},"servers":[{"url":"https://api.oanor.com/centripetal-api","description":"oanor gateway"}],"tags":[{"name":"Circular"},{"name":"Meta"}],"components":{"securitySchemes":{"oanorKey":{"type":"apiKey","in":"header","name":"x-oanor-key","description":"Get your key at https://www.oanor.com/developer/keys"}}},"security":[{"oanorKey":[]}],"paths":{"/v1/angular":{"get":{"operationId":"get_v1_angular","tags":["Circular"],"summary":"Angular kinematics","description":"","parameters":[{"name":"radius","in":"query","required":false,"description":"Radius (m)","schema":{"type":"string"},"example":"5"},{"name":"angular_velocity","in":"query","required":false,"description":"Angular velocity (rad/s)","schema":{"type":"string"}},{"name":"velocity","in":"query","required":false,"description":"Linear velocity (m/s)","schema":{"type":"string"},"example":"10"},{"name":"rpm","in":"query","required":false,"description":"Revolutions per minute","schema":{"type":"string"}},{"name":"frequency","in":"query","required":false,"description":"Frequency (Hz)","schema":{"type":"string"}},{"name":"period","in":"query","required":false,"description":"Period (s)","schema":{"type":"string"}}],"security":[{"oanorKey":[]}],"responses":{"200":{"description":"OK","content":{"application/json":{"example":{"data":{"rpm":19.098593,"note":"ω = 2π·f = 2π/T = v/r. 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