Year 13 - Gravitation Flashcards
Area Under a g - r Graph
The area under the curve represents the Gravitational Potential, V.
Escape Velocity
Escape speedis the minimum velocity/speed with which a mass should be projected from the surface of a body with mass in order to escape the gravitational field.
Geostationary Orbit
The satellite orbits in the plane of the Earth’s equator. The satellite has the same angular velocity as a point on the Earth’s surface. The satellite takes 24 hours to orbit the Earth. The satellite remains over the same point on the Earth’s surface.
Gradient of a V - r Graph
The gradient of a point on the curve represents the Gravitational Field Strength, g.
Gravitational Field
A Region in space where a mass will experience a force.
Gravitational Field Line
The direction in which a test mass would accelerate.
Gravitational Field Strength, g
Gravitational field strengthat a point is defined as the gravitational force per unit mass acting on a test mass placed at that point.
Gravitational Potential Energy
Gravitational potential energy, of a point mass m, in a gravitational field, is the work done by an external force in bringing that mass from infinity to that point.
Gravitational Potential, V
Gravitational potentialat a point in a gravitational field is the work done per unit mass, by an external force, in bringing the mass from infinity to that point.
Kepler’s Third Law
The square of an object’s orbital period (T) is directly proportional to the cube of its orbital radius (r).
Newton’s Law of Universal Gravitation
The force between two masses is directly proportional to the product of their masses and inversely proportional to the square of the distance between centres of mass.
Synchronous Orbit
An orbit in which the period of the orbit is equal to the rotational period of the object that it is orbiting. A Geo-Stationary Orbit is an example of a Synchronous Orbit.
