Moments Flashcards
What is the moment of a force
It is a measure of its tendency to cause a body to rotate (whatever direction) about a specific point or axis
Ie.
The force behind that turning (tipping) effect
What factors determine how strong the turning effect is
- size of force
- Its distance from the pivot
Equation for moments
Nm = F x D
Moments = Force x perpendicular distance from the pivot point
What is unit of moments, or what is it measured in
Nm
Newton metres
What does perpendicular distance mean
horizontal distance
Does the moment of a force act clockwise only
clockwise and anticlockwise
What 2 conditions must moment be in order for an object to be in static equilibrium
just name them
- net moment on object must be 0
- Principle of moments
What is principle of moments, and another name for it
Sum of clockwise moment about any point = sum of anticlocwise moment about the same point
also called rotational equilibrium
What is a couple
2 forces of same size, but acting in opposite directions. There is force equilibrium but no rotational equilibrium
What is a torque
describes turning effect of the couple