• Generally, a?force field?is a region of space in which an object will experience a?force
• A?gravitational field,?therefore, is a region of space in which any object with?mass?experiences a?gravitational force
• The Sun, for example, creates a gravitational field around it
  • The Earth, which has mass, experiences the gravitational force due to the Sun
  • This gravitational force keeps the Earth in orbit around the Sun
• Additional effects of the Moon and Sun's gravitational fields can be seen on Earth, such as the cause of tides

Direction of a Gravitational Field

• The direction of a gravitational field can be represented as a?vector, the direction of which must be determined by inspection
• The direction of the vector shows the direction of the gravitational force that would be exerted on a mass if it was placed at that position in the field
• These vectors are known as?field lines?(or 'lines of force'), which are represented by arrows
  • Therefore, gravitational field lines also show the direction of?acceleration?of a mass placed in the field
• Gravitational field lines are therefore directed toward the centre of mass of a body
  • This is because the gravitational force is?attractive
  • Therefore, masses always attract each other via the gravitational force
• The gravitational field around a point mass will be?radial?in shape and the field lines will always point towards the centre of mass

The direction of the gravitational field is shown by the vector field lines