BRAINCAKEGravitational Fields
Revision notes for Gravitational Fields in OCR Physics A (H556). Every lesson in BrainCake comes with R.E.C.I.P.E. recall steps, a quick check and spaced reviews.
- Gravitational Fields.The mass of an object creates a force field around itself.
- The Strength of a Gravitational Field.The path which a small 'test' mass placed in a gravitational field is called a field line.
- Free fall in a gravitational field.An object with mass m in a gravitational field will experience a gravitational force F = mg which is equal to its weight Provided that no other…
- The Earth's gravitational fieldThere are different types of field: electric, magnetic and gravitational.
- Gravitational Potential EnergyIn order to escape a planet's gravitational pull, a rocket's engine must do work when it rises from the surface of a planet.
- Gravitational Potential.An object has gravitational potential energy due to its position in the earth's gravitational field.
- Equipotentials.Equipotentials are lines that join points with the same gravitational potential.
- The potential gradient.The potential gradient at a point in a gravitational field is the change in gravitational potential per metre.
- Newton's Law of Gravitation.Kepler made measurements of the motion of each planet.
- Gravitational Field Strength - g.The gravitational field strength g at a point is the gravitational force per unit mass acting on a small test mass placed there, g = F/m.
- Gravitational Potential.Starting from the surface of a spherical planet, the gravitational potential at a point a distance - r - from the centre of mass of the planet is…
- Potential GradientsThe gravitational potential gradient at a point is the change in gravitational potential per metre, ΔVg/Δr.
- Area Under a Force vs Distance GraphThe diagram shows the force needed to move a 1kg mass in a gravitational field (N) with the distance moved (m).
- SatellitesIn order for a satellite such as the moon to travel in a circular orbit around a planet there needs to be a centripetal force The centripetal force…
On the specification
- 5.4.1 Point and spherical masses
- 5.4.2 Newton's law of gravitation
- 5.4.3 Planetary motion
- 5.4.4 Gravitational potential and energy