(9th) Newton's first law of motion - inertia Flashcards
What is inertia?
the property to resist changes in motion
define force?
the simplest sense, a push or pull
What does the law of inertia (newton’s first law) state?
Every object continues in its state of res, or of uniform motion in a straight line, unless compelled to change that state by forces impressed upon it
What do you call a quantity that has both magnitude and direction?
vector quantity
What are vector quantities represented as?
by arrows whose length and direction show the magnitude and direction of the quantity
What is tension?
stretching force
when do we consider net force?
when more than two forces are acting upon an object
Define mechanical equilibrium
- the net force is zero on something - the state of an object or system of objects for which there are no changes in motion. If at rest, the state persists. If moving, motion continues without change
what does it mean by support force
the upward force opposite to force of gravity (eg. the weight of the book and the support force must be equal, thus the net force is zero and the objects are in mechanical equilibrium)
What conditions must be met for an object to be at mechanical equilibrium?
1.) the vector sum of all external forces is zero 2.) the sum of the moments of all external forces about any line is zero
What does a bathroom scale measure? What force?
support force (the support force and your weight if you’re on the weighing scale is the same magnitude )
What is equilibrium?
a state of no change
What does the equilibrium rule state?
For any object or system of objects on equilibrium, the sum of the forces acting equal zero. In equation form:
(3 looking E)F = 0
the vector sum of forces = zero
