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Home Minds On Newton's Laws Mission NL1 Inertia and Newton's First Law Help Help 2

Mission NL1 Inertia and Newton's First Law

The Question

Suppose that an astronaut throws a rock in outer space at a location far from significant influences of gravity and air resistance. One would expect that the rock would ...

Physics Rules

Newton's First Law of Motion:
An object at rest will tend to stay at rest; an object in motion will tend to stay in motion with the same speed and direction, unless acted upon by an unbalanced force.

Don't be Fooled

Many beginning students of Physics believe that forces cause objects to move or to keep on moving. But don't be fooled! Forces do not cause objects to move, but rather to change the way they move. Forces, when unbalanced, cause accelerations - changes in the velocity of the object. An object in motion does not need a forward force to sustain its motion. A forward force would only be needed to balance a resistive force in order to maintain a state of motion. In the absence of resistive forces, an object in motion would stay in motion with the same speed and direction.

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