Chapter 2 Summary
Definitions
Dynamic Equilibrium – object moving at a constant speed in a straight line, forces balanced.
- The Ancient Greeks thought that the Earth was stationary and that everything else in the Universe moved relative to the Earth.
- Aristotle Natural Place Theory was so well respected that it influenced scholars for almost 2000 years.
- Galileo theorized that, in the absence of friction, all objects fall at the same rate.
- Galileo's Law of Inertia was refined and advanced by Sir Isaac Newton and it became Newton's First Law of Motion.
- If there is no net force acting on an object, its state of motion will not change.
- The Free Body Diagram is a tool to help identify the forces acting on an object and, perhaps ultimately, to find the Net Force acting on an object.
Definitions
- Inertia – the tendency of an object to continue its state of motion.
- Mass – the physical quantity used to measure an object's inertia.
- Force – a push or a pull exerted on some object.
- Contact force – a force that results from the physical contact between objects.
- Field force – a force that acts over a distance and does not require contact between objects. Examples: gravitational force, electromagnetic force
- Newton – the unit of Force. It is the amount of force necessary to make a 1 kg object accelerate at a rate of 1 m/s every second.
- Equilibrium – a situation where all the forces acting on an object balance each other out so there is no Net force. When there is no net force acting on an object, the object's motion will not change.
Dynamic Equilibrium – object moving at a constant speed in a straight line, forces balanced.
- Weight – the measurement of the force of gravity pulling downward on an object.
- Normal Force – A force exerted by one object on another in a direction perpendicular to the surface of contact. Example: the upward push by a table on a book resting on the table.