Science

Force Calculator

Calculate force (F=ma), work (W=Fd), and power (P=W/t) with unit conversions. Apply Newton’s laws instantly.

Quick Answer

Force = Mass × Acceleration. A 10 kg object under gravity (9.81 m/s²) experiences 98.1 Newtons of force. Work = Force × Distance. Power = Work / Time.

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Results

98.10 N

Force

F = m × a = 10 kg × 9.81 m/s² = 98.10 N

98.10 N

Newtons

22.0538 lbf

Pounds-force

10.0034 kgf

Kilogram-force

9810000 dyn

Dynes

About This Tool

The Force Calculator computes force, work, and power using the fundamental equations of classical mechanics. It supports multiple unit conversions and provides the formula used at each step.

Newton’s Second Law: F = ma

Force equals mass times acceleration. One Newton is the force needed to accelerate 1 kilogram at 1 meter per second squared. On Earth, gravity provides approximately 9.81 m/s² of acceleration, so a 1 kg object weighs about 9.81 N.

Work: W = Fd

Work is force applied over a distance. One Joule equals one Newton applied over one meter. This formula assumes force is applied in the direction of motion. If force is at an angle, multiply by the cosine of the angle.

Power: P = W/t

Power is the rate of doing work. One Watt equals one Joule per second. A 100W light bulb converts 100 Joules of electrical energy per second. One horsepower equals approximately 746 Watts.

Unit Conversions

The calculator converts between SI units and common alternatives. Force: Newtons, pounds-force, kilogram-force, dynes. Work: Joules, kilocalories, foot-pounds, kilowatt-hours. Power: Watts, horsepower, BTU/hour, kilowatts.

Frequently Asked Questions

What is 1 Newton of force?
One Newton is the force needed to accelerate 1 kg at 1 m/s². It's roughly the weight of a small apple (about 102 grams) on Earth.
How do I convert Newtons to pounds?
Multiply Newtons by 0.2248. So 100 N ≈ 22.48 pounds-force. One pound-force equals 4.448 Newtons.
What is the difference between mass and weight?
Mass is the amount of matter (measured in kg). Weight is the gravitational force on that mass (measured in N). A 10 kg mass weighs 98.1 N on Earth but only 16.2 N on the Moon.
How many Watts is one horsepower?
One mechanical horsepower equals 745.7 Watts. A car engine rated at 200 hp produces about 149,140 Watts at peak power.
What is a Joule in everyday terms?
One Joule is roughly the energy needed to lift a small apple (100g) one meter against gravity. A food calorie (kcal) equals 4,184 Joules.

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