Final answer:
The force needed for a 6 kg object depends on the action: no force for constant velocity (A) or to remain at rest (C), a net force calculated by F=ma for acceleration (B), and specific context needed for force under pressure (D).
Step-by-step explanation:
The amount of force required to perform actions on a 6 kg object depends on the specific action and circumstances. Here's a breakdown:
A) To keep an object at a constant velocity, no net force is needed because of Newton's first law of motion, which states that an object in motion will stay in motion at a constant velocity unless acted upon by a net external force.
B) For an object to accelerate, a net force must be applied according to Newton's second law of motion, F=ma, where 'F' is the force applied, 'm' is the mass, and 'a' is the acceleration. The amount of force would depend on the desired acceleration.
C) To keep an object at rest, no net force is required if it is already at rest, again following Newton's first law.
D) When an object is under pressure, it generally refers to a force applied over an area, but to provide a specific force, more context on the pressure situation is needed.