Newton's Laws Study Guides
You'll need to be able to recognize these (and various permutations) on sight:
Ramps
Hanging Objects
Elevators
Dragging Blocks
Hangers & Sliders
  
 

1) Apply Newton's Laws to determine the state of the object in question

  • Is the object at rest (equilibrium, static etc...)?
  • Is the object out of balance, accelerating?
  • Sum of the forces in x....(ALWAYS)
  • Sum of the forces in y... (ALWAYS)
  • Is friction present?

2) Can you assume the object is 'behaving well'?

  • All connected objects are moving together at the same rate?
  • No excessive force is applied that would cause your string to snap, stretch or launch your object off the surface?

3) Is it a WHOLE lot easier to apply a systems analysis?

Formulae Objectus:

∑Fx = max (the sum of the forces acting on an object (or system of objects) in the x direction results in that object (or system of objects) accelerating at a measureable rate in the x direction if the resulting forces are imbalanced)

∑Fy = may (the sum of the forces acting on an object (or system of objects) in the y direction results in that object (or system of objects) accelerating at a measureable rate in the y direction if the resulting forces are imbalanced)