Net force is not proportional to velocity and instead, net force is directly proportional to acceleration, which is the rate of change of velocity, according to Newton's second law.
And so a constant velocity means that an acceleration of 0, results in a net force of 0, regardless of how fast the object is moving.
Acceleration is directly proportional to the net force that is acting on an object, provided that the mass also remains constant.
Doubling the net force on an object, also will double the objects acceleration, while the acceleration is in the same direction as the net force.
If the net force increases, then acceleration increases by the same factor and for a given net force, the acceleration is also inversely proportional to the mass of the object.
The acceleration vector points in the same direction as the net force vector and if the net force is 0, then the acceleration is also 0, which results in constant velocity and if a force that is applied to an object is tripled, the acceleration of the object is also tripled, assuming that the mass also remains unchanged.
Net force is proportional to both the mass or (m) of an object and also it's acceleration (a) which is expressed by the formula of F= ma.
What this means is, that an increase in either mass or an increase in acceleration will result greater requirement of force.
The key proportionality relationships in force and proportional in Newton's second law of motion include.
Acceleration (a) which is when force is directly proportional to acceleration or (F x a).
Mass (m) which is when force is directly proportional to mass (F x m).
Rate of change of momentum, which is when force is directly proportional to the rate of change of momentum which is derived from F = dp
-
dt.
Normal Force like (FN): In friction, frictional force is directly proportional to the normal reaction force.
Product of masses: In gravitational terms, force is also proportional to the product of two masses.
And for Inverse proportionality, Distance Squared or Gravitational force is inversely proportional to the square of the distance between objects.
Newton's second law of motion (also known as the force law ) states that… acceleration is directly proportional to net force when mass is constant, and… acceleration is inversely proportional to mass when net force is constant, and consequently… net force is directly proportional to mass when acceleration is constant.
The force is proportional to the mass of the two interacting objects, and is inversely proportional to the square of the distance between them.
The factors G, M, and r are the same for all masses at the surface of the Earth.