SEHS IB 4.3

The centre of mass of a body is the point at which...

• the force of gravity acts with greatest magnitude

• the body is closest to the Earth surface

• it is balanced in all directions

• it is relaxed

In uniform objects (symmetrical) the centre of mass is the geometric centre. However, in non-uniform shapes it can lie outside the actual body.

• TRUE

• FALSE

In the human form the centre of mass has no fixed point but is dependent on the....

• weight

• position

• body composition

• velocity

Why is the Frosbury Flop so effective?

• it prevents back injuries

• the center of mass is often above the body

• the center of mass is often below the bar

• it is the way cooler than scissors

A lever by itself is not effective. It must have something on which to pivot. This point is called:

• balance point

• falcon

• fulcrum

• balance arm

The image shows:

• 1st class lever

• 2nd class lever

• 3rd class lever

The image shows:

• 1st class lever

• 2nd class lever

• 3rd class lever

Opening the door by a handle is an example of....

• 1st class lever

• 2nd class lever

• 3rd class lever

Biceps curl is an example of...

• 1st class lever

• 2nd class lever

• 3rd class lever

Functions of a lever include increasing the load (or force) and...

• increasing the acceleration with which an object will move

• increasing the velocity with which an object will move

• increasing the distance which an object will move