Gravitaional fields Flashcards
What is Newton’s law of universal gravitation?
Every particle in the universe exerts an attractive force on every other particle.
What is the definition for weight?
The gravitational force that the earth exerts on an object.
What is the relationship between the distance of two masses and the gravitational force?
Inverse square relationship
What is a field?
A 3D space that can be mapped with values of a perameter
What type of field is used for spherical objects?
Radial field, with all the lines pointing towards the centre of mass
How do we represent the strength of a field using field lines?
The density of the lines
How do we represent the direction of a field using field lines?
The direction of the lines
How is the strength of a gravitational field defined?
Gravitational force exerted per unit mass at a point in the field
What are the SI units for gravitational field strength?
Nkg-1
What does the field strength around an object depend on?
The mass of the object and will decrease with proportion to the square of the distance
What happens to the magnitude of g in a radial field?
decreases with distance from the body
What is a uniform field?
Where g is the same all throughout the field
What is a geostationary satellite?
A satellite that keeps the same pace as the object it’s orbiting so it appears to stay in the same place
What can a geostationary satellite be used for?
Communication
What is a polar orbit?
Orbits around both north and south poles
What can polar orbits be used for?
Taking scans of earth and GPS
What is the relationship between time period and radius?
T^2 = r^3
