Newton's Problems

 There are four kinds of Newton's problems that we learned in our physics class, those four are equilibrium, incline, pulley, and train.

Equilibrium happens when there are no acceleration acting on the object and the positive force are equal to the negative force.

Assumptions→↓
 -no air resistance
- no acceleration  ax = 0   ay = 0
- T1y = T2y = mg
-one free body diagram
-Set positive axises

The second Newton's problem is incline. There are two different types of incline, static and kinetic.

Incline (static)

Assumptions→↓

-no air resistance

-no acceleration
-Fn is perpendicular to the surface

-Fgy - Fn = 0
-one free body diagram

The only different between static incline and kinetic incline is the change of acceleration. In kinetic incline, there is acceleration.

Assumptions→↓

- no air resistance

-Acceleration not = 0

-positive in the direction of acceleration
-Fn is perpendicular to the surface
-one free body diagram
-Fn - mgy = 0

Pulley

Assumptions→↓

-pulley is frictionless

-rope frictionless

-no air resistance

-2systems>2 FBDs

-T1 = T2

-a of the system is the same

-positive in the direction of acceleration



Train

Assumptions→↓

-positive in direction of acceleration

-3 FBDs

-no air resistance

-cables weightless

-a is consistant