Term
What is Newton's Law of Universal Gravitation? 

Definition
Newton's Law of Universal Gravitation describes how ALL objects attract each other's mass with a force of gravitational attraction.
The force of gravitational attraction is directly proportional to the masses of each of the objects and inversely proportional to the square of the distance that separates their centers. 


Term
What is the equation for gravitational force of attraction? 

Definition


Term

Definition
The gravitational constant
G = 6.673 x 10^{11} N m^{2} kg^{2} 


Term

Definition
distance between the centres of the masses is denoted by 'r' 


Term

Definition
g is the gravitational field strength or the acceleration due to gravity  depends on the situation! 


Term
What are the units of 'g' 

Definition
When gfs the unit is N kg^{1} but when acceleration due to gravity the unit is that of acceleration m s^{2} 


Term
What is the gravitational field strength at a point? 

Definition
The gravitational force per unit mass at that point. 


Term

Definition
g = F/m
but F = GmM/r^{2}
so, g = GM/r^{2} 


Term
Is Gravitational Field strength a scalar or vector quantity? 

Definition
Gravitational Field strength is a vector because it has a direction  is a force per unit mass (and force is a vector!). 


Term
Is gravitational potential a scalar or a vector? 

Definition
It is a scalar quantity  'energy required' and energy is scalar! 


Term
What is meant by the gravitational potential at a point in a gravitational field? 

Definition
The gravitational potential at a point in a gravitational field is the work done against the field (or energy change) per unit mass [image] when an object is moved from infinity to the point [image] 


Term
State the relationship between the gravitational potential energy, E_{p}, and the gravitational potential, V, for a body of mass m placed in a gravitational field 

Definition
The relationship between them is that Ep equals the product of the mass m and the gravitational potential V
or Graviational potential is gravitational potential energy per unit mass (or per kg) 

