Modelling in Mechanics Flashcards
Particle Assumptions
The mass is concentrated at a single point
Ignore rotational force/air resistance
Smooth Assumptions
No friction
Smooth and Light Pulley Assumptions
No friction, equal tension on either side
Inextensible String Assumptions
The magnitude of the acceleration on each side will be equal
Rod Assumptions
All of the mass is concentrated along a line
Support Assumptions
They act on a single point
Lamina Assumptions
The mass is distributed along a flat surface
Wire Assumptions
Can be treated as one-dimensional
Bead Assumptions
Move freely along a wire or string, tension is the same as on either side
Buoyancy
The upward force on a body that allows it to float or rise when submerged in a liquid
Thrust/Compression in a String
The forward force when an object is pushed along a surface
What to do when you define a problem?
Define your positive directions
Average velocity vs velocity
Average velocity is the total displacement/time, velocity the gradient at a point