Chapter 2: Motion Along A Straight Line Flashcards
What is the purpose of kinematics?
Describing motion without addressing the cause of that motion. It is limited to the study of motion of particles.
What is a particle?
Any object in which every part of that object moves exactly the same way at any instant.
What is position?
A coordinate on a chosen axis, relative to a chosen origin.
SI unit: meter (m)
Symbol: x, y, z
Is position a vector quantity?
Yes!
What is average velocity?
The rate of change of position over a finite time interval–OR displacement divided by a time interval.
SI unit: m/s
Symbol (for x-axis motion): v(avg) = (Δx)/(Δt)
Is velocity a vector quantity?
Yes!
What is displacement?
The total change in position between two points.
SI unit: meter (m)
Symbols: Δx, Δy, Δz
Is displacement a vector quantity?
Yes!
What is instantaneous velocity?
Velocity at a specific instant in time.
SI unit: m/s
symbol (motion along an x-axis): v = dx/dt
What is average acceleration?
The rate of change of velocity over a finite time interval.
SI unit: m/s^2
Symbol: a(avg) = Δv/Δt
Is acceleration a vector quantity?
Yes!
What is instantaneous acceleration?
Acceleration at a specific instant in time.
SI unit: m/s^2
Symbol: a = dv/dt
If acceleration and velocity have the same sign, the particle is ___ while moving in the direction of the velocity!
Speeding up
If acceleration and velocity have opposite signs, the particle is ___ while moving in the direction of the velocity!
Slowing down
What is free-fall motion?
Any motion of a particle under the influence of gravity alone.
All objects in free-fall near a planet’s surface have the same constant ___, independent of the object’s mass.
Acceleration
Acceleration due to gravity is directed ___.
Vertically down
On Earth, this acceleration has magnitude g, or ___.
9.8 m/s^2
Integrating acceleration gives change in ___. Conversely, the derivative of ___ gives acceleration.
Velocity; velocity.
Integrating velocity gives change in ___. Conversely, the derivative of ___ gives velocity.
Position; position.
The three key acceleration equations:
v =(v0)+at
x=(x0)+(v0)t+(1/2)at^2
v^2=(v0)^2+2aΔx
