1.1.7

Calculating Changes in Energy

Test yourself

Calculating Changes in Energy

Energy can be stored in many different ways and the amount of energy stored can be calculated using the following equations:

Illustrative background for Kinetic energyIllustrative background for Kinetic energy ?? "content

Kinetic energy

  • Kinetic energy is the energy stored by an object's movement.
  • The equation for calculating kinetic energy stored is:
    • Kinetic energy = 1/2 × mass × velocity2
    • Ek = 1/2mv2
Illustrative background for UnitsIllustrative background for Units ?? "content

Units

  • Kinetic energy is measured in joules (J).
  • Mass is measured in kilograms (kg).
  • Velocity is measured in metres per second (m/s).
Illustrative background for Gravitational potential energyIllustrative background for Gravitational potential energy ?? "content

Gravitational potential energy

  • Gravitational potential energy is the energy stored in objects raised above the Earth’s surface.
  • This energy exists because of the Earth’s gravitational field.
  • The equation for calculating gravitational potential energy stored is:
    • Change in gravitational potential energy = mass × gravitational field strength × change in height
    • ΔEp = mgΔh
Illustrative background for UnitsIllustrative background for Units ?? "content

Units

  • Gravitational potential energy is measured in joules (J).
  • Mass is measured in kilograms (kg).
  • Gravitational field strength is measured in Newtons per kilogram (N\kg).
  • Height is measured in metres (m).
Illustrative background for Elastic potential energyIllustrative background for Elastic potential energy ?? "content

Elastic potential energy

  • Elastic potential energy is the energy stored when an object is being stretched, compressed or squashed.
  • The equation for calculating elastic potential energy stored is:
    • Ee = 1/2ke2
    • Elastic potential energy = 1/2 × spring constant × extension2
Illustrative background for UnitsIllustrative background for Units ?? "content

Units

  • Elastic potential energy is measured in joules (J).
  • The spring constant is measured in Newtons per metre (N/m).
  • Extension is measured in metres (m).

Jump to other topics

1Energy

2Electricity

3Particle Model of Matter

4Atoms & Radiation

5Forces

5.1Basics of Motion

5.2Forces

5.3Effects of Forces

5.4Pressure

6Waves

7Magnetism

8Astrophysics

Go student ad image

Unlock your full potential with GoStudent tutoring

  • Affordable 1:1 tutoring from the comfort of your home

  • Tutors are matched to your specific learning needs

  • 30+ school subjects covered

Book a free trial lesson