Force Calculator – Newton's Second Law (F = ma)
Calculate force, mass, or acceleration using Newton's Second Law: F = ma.
About This Calculator
Calculate force, mass, or acceleration using Newton's Second Law: F = ma. Use the calculator above for instant results.
Worked Examples
- F = 10 × 9.81 = 98.1 N (weight of 10kg mass)
Answer: 98.1 N
- F = 2000 × 3 = 6,000 N
Answer: 6,000 N
- F = 70 × (9.81+2) = 826.7 N (feels heavier)
Answer: 826.7 N
Who Uses This Calculator?
Apply Newton's Second Law.
Force calculations in design.
Demo Newton's laws.
Calculate braking and acceleration forces.
Common Mistakes to Avoid
❌ Confusing mass and weight
Mass: amount of matter (kg). Weight: force of gravity on that mass (N). Weight = mass × g = kg × 9.81.
❌ Direction of force
Force is a vector with direction. This calculator gives magnitude only.
Frequently Asked Questions
Newton's Second Law?
F = ma. Force (Newtons) = Mass (kg) × Acceleration (m/s²).
What is a Newton?
1 N = 1 kg⋅m/s². The force that accelerates 1 kg at 1 m/s². About the weight of a 100g apple on Earth.
Net force?
F_net = F₁ + F₂ + ... (vector sum of all forces). Net force = 0 means constant velocity (Newton's First Law).