1. Newton’s First Law (Law of Inertia)
Definition:
An object will remain at rest or move in a straight line at
constant speed unless acted upon by an external
unbalanced force.
Explanation:
● Objects do not change their state of motion on their
own.
● Inertia is the resistance of any physical object to a
change in its motion.
Example:
● A book on a table remains at rest until someone
pushes it.
● A moving car stops only when brakes (force) are
applied.
Diagram (left):
● A book on a table stays still unless pushed.
● The force is needed to change its motion.
,
Definition:
An object will remain at rest or move in a straight line at
constant speed unless acted upon by an external
unbalanced force.
Explanation:
● Objects do not change their state of motion on their
own.
● Inertia is the resistance of any physical object to a
change in its motion.
Example:
● A book on a table remains at rest until someone
pushes it.
● A moving car stops only when brakes (force) are
applied.
Diagram (left):
● A book on a table stays still unless pushed.
● The force is needed to change its motion.
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