Gravitational Potential Energy Summary

Gravitational Potential Energy (GPE)

  • Symbol: PEg (or Ug)

  • Definition: Energy stored due to an object's elevation.

Formula for GPE

  • GPE = mgh

    • m = mass (kg)

    • g = acceleration due to gravity (9.81 m/s^2 on Earth)

    • h = height above chosen horizontal zero line.

Horizontal Zero Line

  • User-chosen reference point determining if GPE is:

    • Positive: Object above.

    • Negative: Object below.

    • Zero: Object at the line.

  • Must be identified consistently for each problem.

Important Notes

  • GPE's value depends on the chosen reference line.

  • Often set at ground level or the lowest object point.

  • Units: 1 Joule (J) = 1 Newton-meter (N·m) (kg × m/s² × m = J).