ASVAB · Force and Motion

According to the principle of inertia, what will a moving object do unless a force acts on it?

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Correct answer

Continue moving in a straight line at a constant speed

A Curve to the right
B Continue moving in a straight line at a constant speed
C Stop on its own
D Speed up

Why this is the answer

Inertia is the tendency of an object to resist changes in its state of motion (Newton's first law). An object in motion will continue moving in a straight line at a constant speed unless an unbalanced force acts on it, and an object at rest will stay at rest unless a force moves it. In everyday life, friction and air resistance usually act on moving objects and slow them down, which can make it seem like things stop 'on their own,' but it is actually those forces causing the change. Understanding inertia — objects keep doing what they're doing without a net force — is a key force-and-motion concept.

Source: ASVAB MC, Inertia

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About this topic: Force and Motion

Force and motion questions cover Newton's laws, friction, gravity, acceleration and momentum, usually as pictures of objects being pushed, pulled, dropped or balanced. Identify every force acting before deciding what the object will do. This is one of 13 Mechanical Comprehension questions on force and motion, each with a full explanation on a single study page.

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According to the principle of inertia, what will a moving object do unless a force acts on it?

Why this is the answer

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About this topic: Force and Motion

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