Chapter 4: Forces and Newton's Laws Flashcards
force
push or pull
contact force
when things hit other things (physical contact)
non contact/ action-at-a-distance forces
forces exerted when things aren’t in direct contact
like gravity
mass
magnitude, NO DIRECTION
scalar quantity
used to measure inertia
kg
Newton’s First Law of Motion
objects continue at state of constant velocity (moving or still) unless compelled to change state by net force
net force
vector sum of all forces acting on a body
acts to CHANGE velocity NOT sustain it
inertia
Object’s tendency to stay at rest or stay in motion at constant velocity
measured by mass (object’s mass is quant measure of inertia)
Newton’s Second Law of Motion
when net external force acts on object w/ mass m, resulting acceleration is directly proportional to the net force and has a magnitude that is inversely proportional to the mass.
The direction of the acceleration is the same as the direction of the net force.
external force
forces envrionment exerts on object
internal force
forces one part of the object exerts on another
not included in the equation
Newton’s Third Law of Motion
for every action (force), there is an equal and opposite reaction
aka action-reaction law
types of forces (fundamental)
gravitational
strong nuclear
electroweak: forces exerted by electly charged paricles on each other
fundamental because can only be explained in terms of itself
two types of forces
fundamental
nonfundamental
pick up reading at 4.7
