Newton's Laws (Newton's Laws)

• Newton's 1st Law: A body will remain at rest or in motion at a constant velocity unless acted upon by an external (resultant) force.
• Inertia is the resistance of any object to a change in it's motion.
• If the forces are balanced in Newton's 1st law, then the object will remain in a constant state of movement (stationary or moving).
• Newton's 2nd law can be simplified to 'resultant force = mass × acceleration'.
• Mass is the measure of how much 'matter' is in an object.
• Acceleration is directly proportional to the resultant force. If the resultant force doubles, the acceleration doubles.
• Mass is measured in kilograms (kg).
• Weight is a measure of how large the force of gravity is on an object.
• Weight is measured in Newtons (N).
• Mass does not depend on the location of the object.
• The weight of an object is different depending on the location of the object.
• Weight is a type of force.
• Weight = mass × gravitational field strength.
• Earth's surface gravitational field strength is 10N/Kg (9.81N/Kg rounded up).
• Newton's 3rd Law: In an interaction between two bodies, A and B, the force exerted by body A on body B is equal and opposite to the force exerted by body B on body A.
• No force can act alone.
• The action/reaction pair of forces are always on different objects and so never cancel out.
• When drawing objects accelerating away from each other, drawing a free body diagram may be easier to display these forces.