gravitational fields Flashcards
what do all masses have in common?
All masses have a gravitational field around them
what is a gravitational field?
A gravitational field is a region where any mass experiences a non-contact force
define gravitational field strength
The gravitational force per unit mass
what is a test mass?
A particle with a very small mass that we can use to test a gravitational field assuming that the gravitational field remains as if the test mass isn’t there
what does the length of each GFS vector represent?
The length of each gravitational field strength vector represents the magnitude of the gravitational field strength.
why is a constant gravitational field strength used at the surface?
When close to the surface of a planet the gravitational field appears uniform, using a constant like g is still fairly accurate
the field around a spherical mass is a…
Radial field
what happens to a point in-between 2 gravitational fields?
The 2 forces combine to give a resultant force. in some cases the resultant force is 0.
how do you get the resultant gravitational field strength?
Add the 2 gravitational field strength vectors together
give one way a resultant gravitational field strength can equal to 0
an object being exactly halfway between 2 equal masses
why is the gravitational field strength 0 at the centre of the planet?
Real planets are approximately spherical and their mass is evenly distributed over their entire volume.
the object will experience multiple equal forces towards the surface, however the will all cancel out.
state the relationship of the gravitational field strength at the centre of the planet (below the surface)
Below the surface, the relationship between gravitational field strength and distance is linear (g = r)
