{"success":true,"version":"v1","request":{"tool":"get_calculator_schema","calculator_id":"newtons-second-law"},"result":{"entity_type":"calculator","id":"newtons-second-law","calculator_id":"newtons-second-law","canonical_url":"https://tttkmbb.com/physics/newtons-second-law","name":"Force Calculator","title":"Force Calculator – Newton's Second Law F = m·a and Weight W = m·g in N, kN and lbf","category":"physics","category_name":"Physics","tool_name":"calculate_force","featured_mcp_tool":false,"description":"Computes net force from mass and acceleration with Newton's second law, reported in newtons, kilonewtons and pounds-force, together with the object's weight under standard gravity.","use_when":"You know a mass and its acceleration (or deceleration) and need the net force, or you need an object's weight in newtons or pounds-force from its mass.","do_not_use_when":"You need the gravitational pull between two bodies (use gravitational-force), a spring force (use hookes-law) or the force in circular motion (use centripetal-force).","inputs":[{"name":"mass_kg","label":"Mass","type":"number","unit":"kg","required":true,"exclusive_min":0,"description":"Mass of the object in kilograms.","example":1200},{"name":"acceleration_m_s2","label":"Acceleration","type":"number","unit":"m/s²","required":true,"description":"Acceleration of the mass; negative for deceleration. 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Unit: kg.","type":"number","exclusiveMinimum":0,"examples":[1200],"x-unit":"kg"},"acceleration_m_s2":{"description":"Acceleration of the mass; negative for deceleration. Use 9.80665 for the force needed to hold the object against gravity. Unit: m/s².","type":"number","examples":[3],"x-unit":"m/s²"}},"additionalProperties":false,"required":["mass_kg","acceleration_m_s2"]},"output_schema":{"type":"object","properties":{"force_n":{"description":"Net force F = m·a. Unit: N.","type":"number","x-unit":"N"},"force_kn":{"description":"Force in kilonewtons. Unit: kN.","type":"number","x-unit":"kN"},"force_lbf":{"description":"Force in pounds-force (1 lbf = 4.4482216152605 N). Unit: lbf.","type":"number","x-unit":"lbf"},"weight_n":{"description":"Weight of the mass under standard gravity: m × 9.80665. Unit: N.","type":"number","x-unit":"N"},"weight_lbf":{"description":"Weight in pounds-force. 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F = m·a gives the resultant of all forces; individual forces such as friction or thrust must be combined with vector addition to obtain a."}],"tags":["force","newton's second law","f = ma","weight","newtons","pounds force"],"related":[{"calculator_id":"acceleration","reason":"Get acceleration from velocities and time first."},{"calculator_id":"gravitational-force","reason":"Force between two masses by Newton's law of gravitation."},{"calculator_id":"pressure-force-area","reason":"Divide a force by area to get pressure."}],"links":{"html":"https://tttkmbb.com/physics/newtons-second-law","markdown":"https://tttkmbb.com/physics/newtons-second-law.md","json":"https://tttkmbb.com/physics/newtons-second-law.json","api":"https://tttkmbb.com/api/v1/calculate/newtons-second-law","schema":"https://tttkmbb.com/api/v1/calculators/newtons-second-law","openapi":"https://tttkmbb.com/openapi.json","mcp":"https://tttkmbb.com/mcp"},"version":"v1","updated_at":"2026-09-23"},"timestamp":"2026-09-23T23:30:17Z","next_actions":[{"tool":"run_calculator","calculator_id":"newtons-second-law","reason":"Run Force Calculator with the inputs above."}],"links":{"markdown":"https://tttkmbb.com/physics/newtons-second-law.md"}}