Chapter 2: Motion Along A Straight Line Flashcards
(21 cards)
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
