Moments

A force, or several forces, can cause an object to **rotate**. The turning effect of a force is called its **moment**. The size of the moment of the force is given by:

**M=Fd, Moment of a force=force x distance**

The force on the spanner causes a turning effect or moment on the nut. A larger force or a longer distance would mean a larger moment

To get the

**maximum**moment you need to push at**right angles**to the spanner. Pushing at any other angle means a**smaller**distance, and so a smaller moment

Levers increase the distance from the pivot at which the force is applied. Since **M=Fd** this means less force is needed to get the same moment. This means levers make it easier to do work

Gears are

**circular**discs with ‘**teeth**’ around their edgesTheir teeth

**interlock**so that turning one causes another to turn, in the**opposite**directionThey are used to transmit the

**rotational**effect of a force from one place to**another**Different sized gears can be used to

**change**the**moment**of the force. A force transmitted to a larger gear will cause a**bigger**moment, as the distance to pivot is**greater**The larger gear will turn slower than the smaller gear

A force, or several forces, can cause an object to **rotate**. The turning effect of a force is called its **moment**. The size of the moment of the force is given by:

**M=Fd, Moment of a force=force x distance**

The force on the spanner causes a turning effect or moment on the nut. A larger force or a longer distance would mean a larger moment

To get the

**maximum**moment you need to push at**right angles**to the spanner. Pushing at any other angle means a**smaller**distance, and so a smaller moment

Levers increase the distance from the pivot at which the force is applied. Since **M=Fd** this means less force is needed to get the same moment. This means levers make it easier to do work

Gears are

**circular**discs with ‘**teeth**’ around their edgesTheir teeth

**interlock**so that turning one causes another to turn, in the**opposite**directionThey are used to transmit the

**rotational**effect of a force from one place to**another**Different sized gears can be used to

**change**the**moment**of the force. A force transmitted to a larger gear will cause a**bigger**moment, as the distance to pivot is**greater**The larger gear will turn slower than the smaller gear