Moments Flashcards
What does it mean if an object is not turning (in turns of moments)?
The total clockwise moment must be exactly balanced by the total anticlockwise moment about any pivot
What do you do to work out the tension?
Anticlockwise moment = clockwise moment
Total weight (force) x distance from pivot to centre = force on the other side if the pivot x length of the known weight side
To increase a moment:
Increase the force
Or
Increase the distance from the pivot
Describe the idea behind a simple lever.
Levers increase the distance form the pivot at which the force is applied-so this means less force is needed to get the same moment
That’s why levers are known as force multipliers, they reduce the amount of force that’s needed to get the same moment by increasing the distance
When does a resultant moment occur?
If the line of action of the wight lies outside the base of an object, there will be a resultant moment and the object will tend to topple over
How can you further the tilt of an object before the action line of the weight moves outside the base?
A wider base
A lower centre of mass
If someone sits in the centre of a seasaw, the moment about the pivot is zero. Why?
Because their perpendicular distance to pivot is zero
Aimie site 2m from the centre of a seesaw. Leo weighs twice as much as Aimie. How far from the centre must he sit to balance the seesaw?
1m
Why does hanging heavy bags from the handle of a pushchair make it more likely to topple over?
The bags raise the centre of mass so the pushchair will not have to tile so far before the line of action of the weight moves outside the base
Why do ten-pin bowling pins have a narrow base and a high centre of gravity?
So they are likely to to topple over when hit by a bowling ball
What is a moment?
The turning effect of a force
