Physics C: Week 1



Week 1: Discussed 1-D Kinematics

Day 1:
General introduction to the course

Day 2:
Day 2 Lecture Notes

Chapter 2 One Dimensional Kinematics

 * Vectors --> Quantities with Magnitude + Direction (often connoted with a + or -) {Velocity, displacement, etc.}
 * Scalars --> Quantities with Magnitude ONLY {Time, distance, speed, energy, etc.}

Motion Described Through...

 * Position
 * Velocity
 * Acceleration

Different Types of Motion

 * Translation
 * Rotation
 * Vibration
 * Particle is a point-size object (mass with infinitesimal size)
 * Model object as a particle when every part of it moves in the same direction at the same rate

Position
Δx= x(f) - x(i) Δx can be + or - SI Unit: Meter (m)
 * Location of particle with respect to a chosen "frame of reference"
 * One dimensional x or y axis
 * Displacement(Δx) --> Net change in position during time interval
 * Distance --> Length of path followed (always +)

Velocity
Average velocity {V(bar)} SI Unit: Meters per Second (m/s)
 * V(bar)= Δx/ Δt = {x(f)-x(i)}/Δt Velocity can be + or -
 * Average speed= Total distance/ Total time Always Positive
 * Not always magnitude of V(bar)

Instantaneous Velocity

 * V= lim as Δt approaches 0 of (Δx/Δt) = dx/dt Can be +, -, or 0
 * Instantaneous speed = magnitude of instantaneous velocity

Average Acceleration

 * Rate change velocity/time
 * A(x)=ΔV(x)/Δt= V(x(f))-V(x(i))/Δt SI Unit: Meters per Second squared (m/s^2)

Instantaneous Acceleration
A(x)= Lim as Δt approaches 0 of (ΔV(x)/Δt)= d(V(x))/d(t)= d/dt(dx/dt) = d^2(x)/dt^2
 * Same as slope of velocity vs. time graph at a given instant
 * Position --> Quadratic Velocity--> Linear Acceleration --> Constant

Standard Equations

 * V=d/t
 * V(f)=V(i) + at
 * x(t)=x(i)+V(i)t+1/2at^2
 * V(bar)=V(f)+V(i)/2
 * V(f)^2= V(i)^2+2a(x(f)-x(i)) NO time required!

Displacement

 * Area under velocity vs. time curve
 * When object's velocity/acceleration are in the same direction object is speeding up
 * Different directions --> slowing down

Day 3:
Worked on UT Quest

Tests
This Week Tests: None

Future Tests: 1-D Kinematics Test

Homework
UT Quest # 1 Due: 09/03/12 at 11PM