machines [7] [levers] [body] [comprehension quiz]

The body utilizes three classes of levers: first-class, second-class, and third-class levers. These lever systems are formed by bones, joints, and muscles. The joints acting as the fulcrum, muscles providing the effort (force), and the body part being moved as the load. The term 'FLE' will help you to remember which part of the lever is in the middle. First class lever Fulcrum is in the middle. The term 'FLE' will help you to remember which part of the lever is in the middle. Second class lever Load is in the middle. The term 'FLE' will help you to remember which part of the lever is in the middle. Third class lever Effort is in the middle. When raising your head to head a football the neck muscles provide the effort, the neck is the fulcrum, and the weight of the head is the load. Pushing against the blocks in a sprint start. The ball of the foot acts as the fulcrum, the weight of the body acts as the load and the effort comes from the contraction of the muscle. During a biceps curl, the fulcrum is the elbow joint, the effort comes from the biceps contracting and the resistance is the weight that it may be holding.

Which class of lever does this animation show ? 1st class     2nd class     3rd class Which class of lever does this animation show ? 1st class     2nd class     3rd class Which class of lever does this animation show ? 1st class     2nd class     3rd class

There are 9 pictures in a grid. As you hover over each picture a blue screen appears on which there is some information about what is being shown in the picture. Read this information and look at each picture to make sure you understand. If you want to check how much you understand try the quiz on the right hand side. Hover over the pictures to magnify them to make them easier to see. To start the activity again just refresh the page.