- #1
Noesis
- 101
- 0
When trying to understand moments...two particular things bother me.
First Question
First...if the unit for moment is defined as a force x distance, a Newton-Meter perhaps, what the hell does that mean?
A Newton is very self explanatory...the amount of force needed to accelerate a kilogram of mass to 1 meter per second squared.
But a moment?
It seems as well that it would define some type of force about the axis of rotation...so why even have the meter there? It seems like the meter would just be a scaling factor, should be taken as being dimensionless, and a moment only defined in Newtons about a particular axis and direction?
Second Question
Why in the world do we use the cross product to define a moment vector? And why in the world do we want it to be perpendicular to ANYTHING?
If this is to facilitate our calculations...how are they facilitated? Could this be done differently?
I feel like a little monkey doing the homework problems...as I don't have a true understanding of the subject.
Thanks guys.
First Question
First...if the unit for moment is defined as a force x distance, a Newton-Meter perhaps, what the hell does that mean?
A Newton is very self explanatory...the amount of force needed to accelerate a kilogram of mass to 1 meter per second squared.
But a moment?
It seems as well that it would define some type of force about the axis of rotation...so why even have the meter there? It seems like the meter would just be a scaling factor, should be taken as being dimensionless, and a moment only defined in Newtons about a particular axis and direction?
Second Question
Why in the world do we use the cross product to define a moment vector? And why in the world do we want it to be perpendicular to ANYTHING?
If this is to facilitate our calculations...how are they facilitated? Could this be done differently?
I feel like a little monkey doing the homework problems...as I don't have a true understanding of the subject.
Thanks guys.