Answer:
D. 4 times as great
Explanation:
The inertia of an object is the resistance offered by the object to change in its motion or position.
Then concept of inertia is obtained from Newton's first law of motion which states that an object which is not subjected to any net external force will remain its position of rest or constant velocity of motion until some net external force acts on it. The object at rest will then start to move whereas the object moving at constant velocity will experience a change in its speed or direction of motion.
This reluctance to change position is greater, the more massive an object is as well as the higher the speed of motion of the object. Thus, inertia is directly proportional to the mass of the object as well to the velocity of an object in motion.
From Newton's first law, inertia can be calculated as the force to be overcome to mobile an object, i.e. Inertia = F = ma
Where m is mass of object, a = acceleration of the object.
Objects on the earth's surface experience a constant acceleration, g.
Thus for a 1 kg mass, Inertia = 1 × g
For a 4 kg mass, inertia = 4 × g
The inertia of a 4 kg mass is four times as great as a 1 kg mass.
