Chapter 37-Moments And Centre Of Gravity Flashcards Preview

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Flashcards in Chapter 37-Moments And Centre Of Gravity Deck (13):
1

What is the moment of a force?

A moment of a force is a measure of its turning effect.

2

Name two methods of increasing the turning effect of an object.

1) Increasing the size of the force itself.
2) Increasing the distance from the applied force to the fulcrum.

3

What is the equation of the moment of a force?

Moment of a force = force ✖️ perpendicular distance from the force to the fulcrum.

4

What are levers?

Levers are simple machines that allow us to move or turn things more easily.

5

What does the law of the lever state?

It states that that when a lever is balanced, the sum of the clockwise moments is equal to the sum of the anti-clockwise moments.

6

What is the centre of gravity of an object?

It is the point through which all the weight of the object appears to act.

7

When can an object be balanced?

It can be balanced if supported either at its centre of gravity or at a point vertically above or below its centre of gravity.

8

Where are the centres of gravity of equally shaped symmetrical objects?

At their centres.

9

Name two ways objects can be made stable.

1) Giving them a low centre of gravity.
2) Giving them a wide base.

10

When is a body in stable equilibrium?

If, when slightly moved or tilted, its centre of gravity rises.

11

When is a body in unstable equilibrium?

If, when slightly tilted or moved, its centre of gravity falls.

12

When is a body in neutral equilibrium?

If, when slightly moved or tilted, its centre of gravity neither rises nor falls.

13

When will a body topple?

It will topple if a vertical line through its centre of gravity falls outside its base.