the instantaneous acceleration at any point is equal to the
Front
average acceleration over the entire time interval
Back
equations
Front
*
Back
Speed
Front
--the distance traveled per unit of time
-- unit of velocity
-- v = d/t
Back
Average speed is a
Front
function of total distance and total time
Back
the common force every object on earth experiences
Front
gravity
Back
v = sqr root
Front
2ax
Back
average acceleration 2
Front
vf-vi/tf-ti
Back
vf = vo + at
Front
2
Back
Displacement, Delta X
Front
-- the straight line separation of two points in a specified direction
--contains magnitude AND direction, a number, unit and angle
-- Positive or negative based on location
Back
position vs time graph
Front
--(d-t) or (x-t) graphs
-- slope exact value in m/s
-- positive slope = forward
-- negative slope = down
-- horizontal line = rest (0)
Back
velocity equation
Front
v = vo + at
Back
An automobile with an initial speed of 4.30 m/s accelerates uniformly at a rate of 3.00 m/s2. Find the final speed and the displacement after 5.00 s.
Front
-- vi = 4.30, a = 3.00, Δt = 5.00, Δx = ?, vf = ?
-- solve for vf by using equation 4
-- solve for Δx by using equation 3
Back
A ball is thrown vertically upward with an initial velocity of 30 m/s. What are its position and velocity after 2 s, 4 s, and 7 s
Front
a = -9.8, t = 2, 4, 7, vo = + 30, y =?, v = ?
-- y = (30)t + .5 (-9.8)t^2
-- find v from the equitation that contains v and no x
-- substitute t
v = 10.4, 9.20, 38.6 m/s^2
Back
the acceleration is proportional to the
Front
magnitude of the force
Back
Signs for displacement
Front
-- right of origin is positive
-- left of origin is negative
Back
Distance d
Front
-- the length of the actual path taken by an object
--scalar quantity
--Point A to Point B
Back
velocity vs time graph
Front
- v-t graph
-- slope = rise/run = change in velocity/change in time = acceleration
-- delta y times delta x is equal to delta v times delta t, which is equal to distance
-- area under the curve gives the distance traveled (how much you've changed)
--horizontal line = constant speed
-- whenever you cross the x-axis, you change direction
Back
average speed equals
Front
total path m / time
Back
acceleration of gravity
Front
-9.81 m/s^2 or -32 ft/s^2
Back
xf = xo + .5(vf + vo)t
Front
3
Back
average velocity 1
Front
net displacement (delta x)/ time
m/s
Back
If a person runs forward at 5 m/s and then throws a ball at 3 m/s in the same direction they are running, then how fast is the ball going relative to the ground?
Front
5 m/s + 3 m/s = 8 m/s forward
Back
gravity is always
Front
negative
Back
equation 2
Front
--average acceleration
--vf = vi + aΔt
Back
average velocity equations
Front
xf-xi/tf-ti
vi+vf/2
Back
Velocity
Front
--the displacement per unit of time
-- v = d/t = m/s
-- + or - based on direction of motion
Back
equation 4
Front
--final velocity
-- vf^2=vi^2+2aΔx
Back
displacement equation
Front
vt
Back
converting graphs: displacement (m) to velocity (m/s)
Front
-- find the slope
-- slope = y-axis number
-- linear lines in d-t graph is a horizontal line on v-t
-- 0 displacement/horizontal line = horizontal line at 0
-- curve = constant slope
--* CURVE NEEDS TANGENTIAL LINE
--when drawing, just draw the lines first, then connect the dots
Back
instantaneous velocity
Front
the slope of the tangential line at that point
Back
acceleration
Front
the change in velocity per unit of time
--vector quantity
--speeding up
--slowing down
--turning
Back
converting graphs: v-t to d-t
Front
-- split the graph lines
--take the area
-- linear line of area = a curve on d-t graph, levels out at y-axis (slope of v-t)
--horizontal on v-t =linear line on d-t (go from previous point straight down to -16)
--horizontal line on x-axis is constant speed on d-t (horizontal line)
Back
v^2 =
Front
2ax
Back
converting graphs: v-t to a-t
Front
-- use slope
--horizontal lines on the v-t = horizontal lines on x-axis
-- linear lines slope = y-axis number on a-t
**REMEMBER TO GRAPH LINES FIRST, CONNECT DOTS LATER
Back
the average speed depends ONLY on the
Front
distance traveled and the time required
Back
v = 0
Front
no sign needed
Back
v equation
Front
v = change in x / change in t
Back
the direction of acceleration
Front
is the same as the direction of force
-- a will always have the same sign of F, regardless of velocity
Back
If a person runs forward at 5 m/s and then throws BACKWARDS ball at 3 m/s in the same direction they are running, then how fast is the ball going relative to the ground?
Front
5 m/s + 3 m/s = 2 m/s
Back
t =
Front
v / a
Back
equation 1
Front
--average velocity
--Δx = .5(vi+vf)Δt
Back
xf = xo + vot + .5at^2
Front
1
Back
a equation
Front
a = change in v / change in t
Back
initial velocity
Front
vo
Back
converting graphs: a-t to v-t
Front
--horizontal lines on a-t graph = linear line on v-t
--**y-intercept where horizontal line is at is the slope of linear line
Back
equation 3
Front
-- displacement
-- Δx = viΔt + .5a(Δt)^2
Back
average acceleration 1
Front
vf-vo/tf-to
Back
A runner runs 200 m east, then changes direction and runs 300 m west. If the entire trip takes 60 s, what is the velocity?
Front
8.33 m/s
Back
frame of reference
Front
the speed of every object is relative to something else
Back
a change in velocity requires the application of
Front
force
Back
Section 2
(19 cards)
on a v-t graph, if the diagonal line goes up or down (not toward the x-axis), the velocity is
Front
positive
Back
if the v-t graph has a negative linear line below x-axis
Front
the position will start level, but go down
Back
on an x-t graph, if the line is straight,
Front
the object has a constant velocity/speed
Back
on a v-t graph, If the diagonal line approaches the time axis (either from above or below), then the object is
Front
slowing down
Back
vf^2 = vo^2 + 2a(xf - xo)
Front
4
Back
average velocity 2
Front
displacement/time
Back
if teh v-t graph has a positive linear line below x-axis
Front
the position will be half a c
Back
the steeper the slope,
Front
the greater the velocity
Back
if the object is speeding up, then its acceleration
Front
is moving in the same direction as the object
Back
if the position graph has a curve
Front
the velocity will have a linear line
(if the curve goes up/positive, the line will be positive. if the curve levels out, the line is negative)
Back
accelerating object in represented by a ________ line on an x-t graph
Front
curved
Back
v =
Front
x/t
Back
an object that is speeding up and increases its velocity has a higher
Front
magnitude (longer arrows)
Back
a =
Front
v/t
Back
determine displacement from a v-t graph
Front
take the area
Back
if a curved line becomes flatter over time, the accelerating object is
steeper
Front
slowing down
speeding up
Back
if the position graph has a linear slope
Front
the velocity remains constant
(if the slope is positive, the velocity will be above the x-axis)