4-6 Flashcards
Displacement & Velocity
study of motion
mechanics
Displacement & Velocity
description of motion or how it moves
kinematics
Displacement & Velocity
explaining motion or what are the forces that brings into motion
dynamics
Displacement & Velocity
treating objects as particles (points) to make things simple
idealization
Displacement & Velocity
always has a reference point to the actual location of object or points from common reference point
position
Displacement & Velocity
initial to final position or shortest directed distance & path independent
displacement
Displacement & Velocity
length of the path you took & path dependent
distance
Displacement & Velocity
the areas of velocity vs. time curve
displacement
Displacement & Velocity
when an object is moving with the same rate of change of velocity
constant acceleration
Displacement & Velocity
the areas of acceleration vs. time curve
velocity
Displacement & Velocity
is a scalar quantity that states when and how long the motion occurs
time
Displacement & Velocity
is used in referring to a specific time an object is at a particular point
time interval
∆t = t2 − t1
Displacement & Velocity
refers to the time rate change of an object’s
position between its initial and final positions
average velocity
vav−x = x2 − x1/t2 − t1 = ∆x/∆t
Displacement & Velocity
is the slope of the line connecting x1 and x2
average velocity
represents the time progression of an object’s position (report motion)
position time (x-t) graph
velocity at a specific instant in time and is the slope of the tangent line in the x-t graph (average velocity)
instantaneous velocity
is the slope of the line joining v1 and v2 (average acceleration)
velocity-time (v-t) graph
acceleration at a specific instant in time and slope of the tangent line in the v-t graph
instantaneous acceleration
Acceleration
is the rate of change of velocity with time
acceleration
Acceleration
the slope in velocity vs. time graph represented by
acceleration
Acceleration
accelerates in the direction of velocity means
speeding up
Acceleration
accelerates against the velocity means
slowing down
Acceleration
accelerates at a direction that neither parallel or anti-parallel its motion means
change in direction
Acceleration
(+) velocity, (-) acceleration
(-) velocity, (+) acceleration
slowing down
Acceleration
(+) velocity, (+) acceleration
(-) velocity, (-) acceleration
speeding up
Uniformly Accelerated Motion and Free Fall
if an object has a constant acceleration, the instantaneous acceleration is equal to the average acceleration
uniform acceleration
Uniformly Accelerated Motion and Free Fall
constant acceleration of a body falling under the influence of the earth’s gravitational attraction
free fall
Uniformly Accelerated Motion and Free Fall
- gravitational pull of Earth results accelerated falling motion
- acceleration of object varies with distance from Earth’s surface
- acceleration does not vary with mass
- constant acceleration due to gravity is 9.8 m/s^2
- any falling body will experience air resistance, slowing down its motion
Freefall Facts
Uniformly Accelerated Motion and Free Fall
- neglect air resistance
- all bodies at a particular location fall with the same downward acceleration regardless of size and shape
- distance of fall is smaller than radius of the Earth
- ignore effects due to the earth’s rotation
Freefall Assumptions
