mech 2:equilibrium and moments

What is the definition of torque and moment?

What is the equation for the moment of force and its units?

Torque is the turning effect of the force

Moment is the force multiplied by the perpendicular distance from the line of action of the force to the pivot point

Moment =Fd or mgd or mad

In Nm

How can you increase the moment?

Either increase the force or increase the perpendicular distance from the pivot point

What is the equation for a moment at a given angle?

F cos theta x perpendicular distance

It’s cosine bc it’s a perpendicular component

What’s the definition of a couple?

A pair of forces equal in magnitude and opposite and direction which are separated by a perpendicular distance

What is the difference between the force net = zero and the net moment = zero?

The force net means that there was no resultant force

The net moment means there is zero result in the moment about any point

What is the principle of moments?

The sum of the clockwise is equal to the anticlockwise moment about a point

What is the centre of mass and characteristics

The point in a body where the whole way appears to act and is always balance so the net moment will equal zero

The scent of mass can also be outside of the body

For regular objects you just use the geometric centre, irregular objects use a plum line. With any size and shapem the centre of mass traces out a parabolic path.

When it asked for the moment due to north or weight, what would this be and why?

It would always = zero because there is no perpendicular distance, it is vertical.

Only when I asked for the moment due to the vertical component of force, what equation do you use?

F sin theta x distance between f and support beam

How do you know where the force is turning anticlockwise or clockwise?

When you have a pivot point or a beam that is as supported by think of it as if you push it down or upwards where would that force be heading to left or right

If the question asked the reaction force of the pillars when the object is 1/4 or 2/3 et cetera, what does this mean?

It’s Talking about the distance away from the pillar

How do you calculate the moment on a beam if there are two beam

First, you have to letter one A and one B

Then you take moment from B

that means you do B weight x the distance from A= (F1 x Distance from A)+ (F2 x Distance from A) etc

Then make B the subject

To find the moment from A, you do Fr-B