Answer
Inertia is not a force which acts on an object. Inertia refers to the motion of an object that continues along the original direction of motion until some force acts on the object and causes an acceleration according to Newton's second law F = ma.
According to Newton's first law, as long as there is no net force acting on an object, then an object's inertia keeps it moving at a constant speed along its original direction of motion.
Note that inertia can also refer to an object at rest that stays at rest unless a net force acts on the object.
Work Step by Step
Inertia is not a force which acts on an object. Inertia refers to the motion of an object that continues along the original direction of motion until some force acts on the object and causes an acceleration according to Newton's second law F = ma.
According to Newton's first law, as long as there is no net force acting on an object, then an object's inertia keeps it moving at a constant speed along its original direction of motion.
Note that inertia can also refer to an object at rest that stays at rest unless a net force acts on the object.
