Because you never see objects moving forever. If you roll a ball across a table then a force causes it slow down and stop called friction.
Moving objects are usually subject to an unbalanced friction force. The net force on the object is thus not zero.
Newtons laws of motion
Neither is true. It applies to both.
Newtons thrid law of motion is that every action has an opposite and equal reaction acting upon it
An object in motion will not change its motion unless acted on by an external force. This applies to zero motion also.
Gravity
Newtons laws of motion
Newton's First Law called the Law of Inertia, deals with objects having constant motion staying in a straight-line.
newtons laws are idealised and don't involve external forces like friction and air resistance
Neither is true. It applies to both.
Newton's first law of motion categorizes any force affecting the motion as an external force. Friction being an external force, negates its presence as an integral force of a motion. Hence friction cannot be used to observe first law of motion.
Balanced forces keep object in its state of motion (moving or at stop). An objects state of motion can be altered when it is subjected to an unbalanced force. This reflects Newtons first law of motion.
For every action there is a equal and opposite reaction... aka newtons 3rd law of motion. hoped that helped :)
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Yes
It is the type of motion explained in Newtons three laws. Objects acting on one another on a pool table. Cause and effect of physical happenings. Lever, inclined plane, fulcrum, etc. in action.
Newtons thrid law of motion is that every action has an opposite and equal reaction acting upon it
An object in motion will not change its motion unless acted on by an external force. This applies to zero motion also.