Intorduction To Forces: Non Contact + Contact + Vector And Scalar Quantities Flashcards
To understand forces, we must understand vector and scalar quantities. Define vector quantities.
Vector quantities are those which have both magnitude and direction
Lots of vectors are physical quantities. List examples of vector quantities
Force (which is why we need to know v and s quantities. So we can understand force)
Velocity
Displacement
Acceleration
Momentum
Define what a scalar quantity is
Scalars are quantities which have only magnitude and not direction
Some physical quantities are also scalar. List examples.
Speed
Time
Mass
Distance
Temperature
Vectors are normally represented by arrows. Explain how that works. (hint: properties of the arrow)
The length of the arrow represent the magnitude of the quantity and the way in which the arrow faces represents the direction.
Vectors are represented by arrows. How does this link to forces.
Force diagrams often involve arrows and force is a vector quantity.
Which would it mean if the length of arrows attached to two objects are the same?
The vector quantity would have the same magnitude as the length of arrow represents magnitude.
How would the arrows look if the direction of two objects were different?
They would be facing opposite directions. So not the same.
Define a force
A force is a push or pull on an object that is caused by it interacting with something
All forces have to be either non contact or contact. What makes a force a contact force?
If two objects have to be touching for the force to occur/act than that force is a contact force
List some examples of contact forces
Friction
Air resistance
Tension in ropes
Normal contact force
All forces have to be either non contact or contact. What makes a force a non contact force?
If a force can occur without the two objects touching, then that force is a non contact force
List some examples of non contact forces
Magnetic forces
Gravitational forces
Electrostatic forces
What is an interaction pair?
When two objects interact with each other, a force is exerted on both of those objects. And an interaction pair are a pair of forces (equal and opposite) acting on two interacting objects
True or false: interaction pairs can be of the same force. Explain.
True: the forces acting on an object could be the same force and they could also be a different force. As long as they’re equal and opposite.
What is a reaction force?
In other words, it’s the force that acts back with. Let’s say a book was on the table. The force of the book on the table is the original force and the table will also push against the book and that force is the reaction force. It “reacted” to the original force
What is an action force?
It’s the original force. If a book was on a table, the force that the book acts upon the table is the action force. It’s the original force that acts upon an abject
If a book was placed on a table and exerted a force on the table and the table exerted an equal yet opposite five won the book which force is the action force and which is the reaction force.
Action is the force the book exerts on the table and reaction is the force the table exerts on the book
What do reaction and action forces come together to form?
An interaction pair, also known as the action-reaction pair
Define interaction pair
A set of two forces that are in opposite direction with equal magnitude and are acting on different objects
