Newton's First Law
Newton’s First Law
- Force is a push or pull exerted on
- Forces are described not only by how strong they are, but also by the
direction in which they act.
- Forces can be combined.
- When two or
more forces act in the different directions, they add together, but it’s like adding a positive and negative number.
- Equal forces acting on one object in opposite directions are called balanced
- Balanced forces acting on an object will not change the object’s motion.
- The overall force on an object after all the forces are added together is called
the net force.
- When there is a net force acting on an object, the forces are
said to be unbalanced.
- Unbalanced forces can cause an object to start moving, stop
moving, or change direction.
- Unbalanced forces acting on an object will change the object’s
motion (causes acceleration).
- Force is needed only to change the motion of an object.
- Whether an object
is moving or at rest, every object resists any change to its motion.
- Inertia is the tendency of an object to resist change in its motion.
- Newton’s first law of motion states than an object at rest will remain at rest, and an object that is
moving at a constant velocity will continue moving at constant velocity unless acted upon by an unbalanced force.
- Newton’s first law of motion is also called the law of inertia.
- Mass is the amount of matter in an
- The SI unit of mass is the kilogram (kg).
- The amount of inertia an object has depends on its mass.
- The greater the mass
of an object, the greater its inertia