Assumptions Flashcards
(14 cards)
1
Q
Particle
A
- dimensions are negligible
- mass is concentrated at a single point
- rotational forces ignored
- air resistance ignored
2
Q
Rod
A
- all dimensions but one are negligible
- mass concentrated along a line
- no thickness
- rigid
3
Q
Lamina
A
- negligible thickness
- mass distributed along flat surface
4
Q
Uniform body
A
Mass of object is concentrated at the centre of the body at a single point
5
Q
Light object
A
- mass small compared to other objects
- zero mass
- tension is the same at both ends
6
Q
Inextensible string
A
- does not stretch
- acceleration is uniform
7
Q
Smooth surface
A
- No friction between the surface and object
8
Q
Rough surface
A
- objects in contact with the surface experience friction
9
Q
Wire
A
- rigid thin length if metal
- one dimensional
10
Q
smooth and light pulley
A
- no mass
- tension same either side of pulley
11
Q
bead
A
- particle with hole in it
- moves freely along wire
- tension same either side of bead
12
Q
peg
A
- support from which a body can be rested
- dimensionless and fixed
- can be rough or smooth
13
Q
Air resistance
A
- experienced when an object moves through the air
- usually modelled as negligible
14
Q
gravity
A
- g
- 9.8ms^-2
- assume all objects with mass attracted to earth by this
- uniform and acts vertically downward
- constant unless stated otherwise
