Chapter 2 - Mechanical Equilibrium Flashcards
What is a force?
A push or a pull.
What is the net force?
The sum of all the forces acting on an object.
If an object has 18N of force pushing on it’s right side and an opposite force of 14N pushing on its left side, what is the net force acting on the object?
4N to the right.
What is a vector?
An arrow that represents the magnitude and direction of a quantity.
How are vector quantities and scalar quantities different?
Vectors must have both magnitude and direction whereas scalers have only magnitude and no direction.
What is the equilibrium rule?
Whenever the sum of all forces acting on an object equals zero, the object is in mechanical equilibrium.
What is the support force and what’s another term for it?
The upward force that balances the weight of an object on a surface. The normal force.
For an object at rest on a horizontal surface, what is the support force equal to?
The weight of the object (due to the downward pull of gravity.)
What is a resultant?
The sum of two or more vectors.
How are static and dynamic equilibrium different?
Objects at rest are said to be in static equilibrium; objects moving at constant speed in a straight-line path are said to be in dynamic equilibrium.
Can an object be moving and yet still have the net force acting on it equal zero?
Yes. It’s called dynamic equilibrium.
Describe the Parallelogram Rule
To find the resultant of two non-parallel vectors, construct a parallelogram wherein the two vectors are adjacent sides. The diagonal of the parallelogram shows the resultant.
If a traffic light is suspended by two cables, as the angle between the two cables increases does the tension in the cables increase or decrease?
Increases
If a traffic light is suspended by two cables at different angles to the horizontal, which cable has the greater tension?
The more vertical cable.
