Question

state the newton's first law of motion

Answer 1

"Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it."

Translation: An object in motion stays in motion unless acted upon by an external force, and an object at rest stays at rest unless acted upon by an external force. Unless acted upon by an external force, an object will not accelerate (slow down or speed up). The only reason we don't see this every day is because of friction with a surface or air resistance - these are external forces that slow a ball or a car.

Answer 2

Sir Isaac Newton first presented his three laws of motion in the "Principil Mathematical Philosophiae Naturalis" in 1686. His first law states that every object remains at rest or in uniform motion in a straight line unless compelled to change its state by the action of an external force. This is normally taken as the definition of inertia. The key point here is that if there is no net force acting on an object (if all the external forces cancel each other out) then the object maintains a constant velocity. If that velocity is zero, then the object remains at rest. If the velocity is not zero, then the object maintains that velocity and travels in a straight line. If a net external force is applied, the velocity changes because of the force.

Answer 3

Kudos to Underhill for his answer.

Paul, if you already knew the answer, please don't spam this group with such elementary questions.