physics midterm Flashcards
vf
Vo + at
change in X
Vot + .5at^
Vf^
Vo^ + 2aX
calculate how fast an object free falls
v=g x t
object droped
height=
.5gt^
projectile
only force is gravity
horizontal component
no acceleration gravity has no effect
d=vt
vertical component
acceleration is 10
use all formulas
to find time y=.5gt^
angled launches
at max hieght
velocity of horizontal and vertical is the same
speed is equal at equal heights
newton’s first law
object at rest will stay at rest unless outside force
2nd law
force= mass x acceleration
3rd law
every action has an equal or opposite reaction
force pairs
object cannot create a force alone
unit of length
meter
unit of mass
kilograms
unit of time
seconds
velocity
length/time
acceleration
length/time^
x=
.5at^
acceleration towards the center of motion
a= v^/r
significant figures
multiply: answer same number of SF as the lowest # of SI
add: number of decimal places in the answer is equal to the smallest number of deconmal places
dynamics
study of motion
kinematics
part of dynamics that describes motion
not causes
displacement
velocity
acceleration
displacement
change in position
Xf-Xi
negative direction or positive direction
vector: magnitude n direction
scalar quantity
magnitude no direction
mass
temp
speed
average speed
total length/total time
includes distance
use distance formula
always positive
scalar
average velocity
displacement
use formula: Xf-Xi
vector
position v time graph
curve: velocity
straight: constant velocity
if curved then just find straight line btw 2 points
instanteous velocity
tangent line
acceleration
change in velocity
directly proportional to net force
average accel
change in v/ change in t
vector
nonzero accel when v is zero: toss a ball up
velocity v time graph
slope of tangent at that point= instantanous accel= accel
inertia
tendency to continue original state of motion
mass
measure of object’s resistance to changes in motion due to force
greater mass, less accel
gravitational force
attraction btw two objects
G x m1m2
r^
r: distance btw object
universial gravitational constant
6.67 x 10^-11
weight force
G x Me m
r^
forces
F=f
accel=0
F is bigger, object accelerates in that direction
how to find max static friction
and kinetic friction
f=un
mechanical energy
sum of KE and PE
work
done only when object is moved through displacement while force is applied. when force or displacement double, work is doubled. double both: quadriple work
W=Fd
force is parallel to displacement
joules
if negative, object loses mechanicle energy
scalar
work when force is at an angle
W= (Fcos@)d
d= always positive
negative/positive work depends on cos@
work net
KEf-KEi
+ answe:
KE
.5mv^ joules
mass moving
scalar
can do work on another object
conservative force
gravity
energy put in same as energy get out
if work it does moving an object btw two points is the same no matter that path
nonconservative force
energy disperse as heat/sound
potential energy
from conservative forces
present at the beginning and end points of a curve
composed of systems
work with gravity
Fdcos@
GPE
mgy
total mechanical energy conserved
KEi + PEi = KEf + PEf
power average
rate at which energy is transferred
w/t
instantaneous power
Fu
force n velocity is parralel
