Calculate kinetic energy (½mv²) or gravitational potential energy (mgh).
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How do you calculate kinetic and potential energy?
Kinetic energy KE = ½ · m · v² and gravitational potential energy PE = m · g · h, where m is mass (kg), v velocity (m/s), h height (m) and g gravity (m/s²). For example, a 2 kg object at 3 m/s has KE = ½ × 2 × 3² = 9 J; raised 10 m it has PE = 2 × 9.81 × 10 ≈ 196.2 J.
Understanding your result
Kinetic energy is the energy of movement and grows with the square of speed. Potential energy is stored by position in a gravitational field. One joule equals one kilogram-metre-squared per second-squared (kg·m²/s²).
Formula and method
Kinetic energy KE = ½ · m · v². Gravitational potential energy PE = m · g · h, where m is mass (kg), v velocity (m/s), h height (m) and g gravity (m/s²).
Worked example
A 2 kg object at 3 m/s has KE = ½ × 2 × 3² = 9 J; raised 10 m it has PE = 2 × 9.81 × 10 ≈ 196.2 J.
How to use this tool
- Choose kinetic or potential energy.
- Enter the mass and the velocity or height.
- Read the energy in joules.
Common mistakes to avoid
- Forgetting to square the velocity for kinetic energy.
- Using grams instead of kilograms for mass.
About the Kinetic & Potential Energy Calculator
This calculator works out mechanical energy in joules. Find kinetic energy from an object’s mass and velocity, or gravitational potential energy from its mass and height above a reference point.
Who should use this tool
Physics students, teachers and engineers checking energy in motion or storage problems.
Benefits
- Kinetic and potential energy in one tool.
- Adjustable gravity for other planets.
- Shows the formula and the working.
- Results in joules and kilojoules.
Practical use cases
- Energy of a moving vehicle or ball.
- Stored energy of a raised mass.
- Checking conservation-of-energy homework.
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Frequently asked questions
What units does this use?
SI units: mass in kilograms, velocity in metres per second, height in metres and energy in joules.
Why does doubling speed quadruple the energy?
Because kinetic energy depends on velocity squared — 2² = 4 — so twice the speed means four times the kinetic energy.