Physics P3 2.1 Moments.

HideShow resource information
What is the moment of a force?
A measure of the turning effect of the force on an object.
1 of 13
What equation is used to determine the size of the moment?
M = F x d.
2 of 13
How can the moment of a force (F) be increased?
To increase the moment of a force (F), increase F or increase d. Meaning increase either the force or the distance to the pivot.
3 of 13
What is the turning effect of a force called?
Its moment.
4 of 13
In the equation for the size of the moment, what is M?
The moment of the force in newton-metres (Nm).
5 of 13
In the equation for the size of the moment, what is F?
The force in newtons (N).
6 of 13
In the equation for the size of the moment, what is d?
The perpendicular distance from the line of action of the force to the pivot in metres (m).
7 of 13
Why is it easier to undo a wheel-nut by pushing on the end of a long spanner than a short one?
Because the long spanner increases the distance between the line of action of the force and the pivot.
8 of 13
Why do we use a lever to make a job easier?
When using a lever, the force we are trying to move is called the load and the force applied to the lever is the effort. A lever acts as a force multiplier, so the effort we apply can be much less than the load.
9 of 13
A door opens when you apply a force of 20N at right angles to it, 0.6m from the hinge. What is the moment of the force about the hinge?
12 Nm.
10 of 13
What force would be needed to open the door if it were applied 0.3m from the hinge?
40 N.
11 of 13
**IN EXAMS, MOMENT MAY BE APPLIED TO LOTS OF DIFFERENT SITUATIONS BUT THE IDEA IS ALWAYS THE SAME: FOR ANY PARTICULAR FORCE MAKE THE DISTANCE TO THE PIVOT BIGGER TO MAKE THE MOMENT BIGGER**
**EXAMPLES OF SITUATIONS THAT MAY BE USED INCLUDE: OPENING A DOOR OR A CAN OF PAINT, MOVING SOMETHING HEAVY IN A WHEELBARROW, USING A CROWBAR OR A SPANNER**
12 of 13
**THE MOMENT EQUATION USES THE TERM 'PERPENDICULAR DISTANCE'' WHICH MEANS THE SHORTEST DISTANCE FROM THE LINE THAT THE FORCE ACTS ALONG**
**LOOK UP DIAGRAMS ETC**
13 of 13

Other cards in this set

Card 2

Front

What equation is used to determine the size of the moment?

Back

M = F x d.

Card 3

Front

How can the moment of a force (F) be increased?

Back

Preview of the front of card 3

Card 4

Front

What is the turning effect of a force called?

Back

Preview of the front of card 4

Card 5

Front

In the equation for the size of the moment, what is M?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Physics resources:

See all Physics resources »See all Forces and Motion resources »