Dynamics Flashcards
Object that only has the force of gravity acting on it
a projectile
The path of a projectile
trajectory
What is the direction of the net force of a projectile
Down so its acceleration is always down
What is the horizontal components velocity
Constant
Dx = Vxt
How is the vertical components velocity changing
Changing at a rate of 9.8 m/s2 [down]
How do you solve for the vertical components of a projectile
The 5 kinematic equations
What is the trajectory of a projectile near the Earths surface
A parabola
What is force
A push or pull on an object
- vector quantity
What is force measured in
newtons (N)
Applied force
contact force provided ONTO an object by a DIFFERENT object
Force of friction
Contact force created by TWO SURFACES RUBBING
Force of gravity
Non-contact force exists between every pair of objects
- called WEIGHT
Fg = mg
Normal force
ALWAYS 90 to the surface
Force of Tension
Contact PULLING force created by strings, ropes ,etc
Galileo’s Law of Inertia
- object in motion tends to stay in motion
- object at rest tends to stay at rest
What is Inertia
- measure of an object’s ability to RESIST changes to its motion
What affects inertia
- the MASS of an object determines the amount of inertia it has
Newton’s 1st Law
If Fnet = O, then v = constant
Static friction
- must be overcome to pull an object and get it in motion
-always greater than kinetic friction
Kinetic Friction
once object is motion this is the frictional force
Ff
magnitude of force of friction Ff = uFn = umg
u
coefficent of friction NO UNITS
- rougher = higher coefficent
- smoother = lower coefficent
Newton’s 2nd Law
If there is a non-zero net force the object will ACCELERATE
Acceleration is
- same direction as net
- proportional to net
- inversely proportional to the mass
