Physics Lect 3

Card Set Information

Author:
laskiru
ID:
58868
Filename:
Physics Lect 3
Updated:
2011-01-09 22:37:01
Tags:
Equilibrium Torque Energy
Folders:

Description:
Equilibrium, Torque, & Energy
Show Answers:

Home > Flashcards > Print Preview

The flashcards below were created by user laskiru on FreezingBlue Flashcards. What would you like to do?


  1. Equilibrium (in Physics)
    • no translational (straight line) or angular (rotational) acceleration
    • therefore: moving at a constant velocity
    • * when a system is not in equilib, write it as if it were (i.e. Fup = Fdown) and then add "ma" to the side with less force (i.e. the direction it is moving in)
  2. Torque
    • T = F l
    • F: force
    • l : lever arm
    • Tcw = Tccw
    • * remember that the "mg" of objects acts at the center of gravity!
  3. Energy
    1) Non Mechanical Energy

    • 2) Mechanical Energy
    • a) Kinetic K = 0.5 mv2

    • b) Potential
    • ** i) Gravitational Ug = mgh
    • ** ii) Elastic Ue = 0.5 k Δx
  4. Work
    • W = Fd cos θ
    • Friction changes the internal energy of an object and it is therefore a form of work (Not Heat)
    • W = ΔK + ΔU + ΔEi
  5. Conservative Forces
    • i.e. gravity, Hooke's Law, electo & magnetic field forces
    • Δ E is the same for any path!
    • when only conservative forces are at work: 0 = ΔK + ΔU
  6. Nonconservative Forces
    • kinetic friction, pushing/pulling forces
    • when nonconservative forces are at work: W = ΔK + ΔU
  7. Power
    • P = ΔE / t
    • P = ΔW / t
    • instantaneous power due to force is Pinst = F v cosθ
  8. Friction as Work
    Fk d cosθ = ΔK + ΔU

What would you like to do?

Home > Flashcards > Print Preview