Newton's Third Law Lecture Notes

Vocabulary flashcards covering the concepts, definitions, and mathematical values associated with Newton's Third Law as presented in the lecture.

Newton’s third law

States that for every action, there is an equal and opposite reaction.

Action-reaction pairs

Forces that always come in pairs whenever two objects interact, such that the two forces are equal in magnitude and opposite in direction.

Logger Pro

The computer software used to record forces from the force probe demonstration in real time.

Criss-crossing nouns

A method used to determine an action-reaction pair by swapping the objects involved; for example, if a bat hits a ball, the reaction is the ball hitting the bat.

System

Any collection of objects that we define for the purpose of analysis.

External force

A force acting on an object or collection of objects from outside the defined system.

Thrust

The reaction force that causes a rocket or jet to move upward or forward as a result of gases being pushed out of the engine.

Inertia

The property of an object that makes it resist changes in its motion; massive objects like buildings or the Earth have high levels of this.

Mass of the ping-pong ball

The value used in the demonstration, which is $10\,\text{g}$ or $0.01\,\text{kg}$.

Acceleration of the ball

The rate of change in motion for the ping-pong ball caused by Earth’s gravitational field, given as $9.8\,\text{m/s}^2$.

Net force on the ball

The amount of force the Earth pulls down on the ball with, calculated to be $0.098\,\text{N}$.

Mass of the Earth

The planetary mass constant used in the lecture, expressed as $6 \times 10^{24}\,\text{kg}$.

Acceleration of the Earth

The calculated change in Earth's motion due to the pull of a ping-pong ball, which is $1.6 \times 10^{-26}\,\text{m/s}^2$.