A compound machine is a combination of two or more simple machines.

A wedge is two inclined planes placed back-to-back. A wedge allows you to push through and cut apart substances with less force than you would need to push through or pull the substance apart without the wedge.

An inclined plane is a flat supporting surface tilted at an angle, with one end higher than the other. There are two elements in an inclined plane: the slope and the rise. In the example to the right, the slope (incline) is represented by the ramp.

Referring to the Figure, F = W sin θ. In this representation of an inclined plane, D represents a block to be moved up the plane, F represents the force required to move the block, and W represents the weight of the block. Expressed mathematically, and assuming the plane to be without friction, F = W sin θ.

The simple machines are the inclined plane, lever, wedge, wheel and axle, pulley, and screw. Six simple machines for transforming energy into work.

Pulleys and wheels and axles, for example, are really special kinds of levers, and wedges and screws are special kinds of inclined planes. Chisels, knives, hatches, carpenter’s planes, and axes are all examples of a wedge.

A chisel is an example of a wedge. Crowbars can be used as any of the three lever classes but the curved end is usually used as a first-class lever, and the flat end as a second class lever.

Yes, knife is a class III lever, as here the effort(i.e. exerted by hands while cutting) is situated between fulcrum and load.

In this case, the axe blade splits the piece of wood into two parts. The leg below is acting as a third-class lever. The effort is between the fulcrum and the load.

There are three types of lever.

• First class lever – the fulcrum is in the middle of the effort and the load.
• Second class lever – the load is in the middle between the fulcrum and the effort.
• Third class lever – the effort is in the middle between the fulcrum and the load.

Overall, third-class levers are the least efficient lever type (Figures E and F). It is a long lever, with the load located as far from the fulcrum as possible. However, if we move the barbell lower along the back, as in the low-bar back squat, we shorten the effective length of the lever, decreasing its inefficiency.

The elbow joint is an example of a third class lever, operating with the effort between the load and fulcrum. The distance between the elbow joint and the insertion site of the bicep tendon is very small, especially when it’s compared to the distance between the elbow joint and the weight in your hand.

The biceps attach between the fulcrum (the elbow joint) and the load, meaning a biceps curl uses a third class lever. The triceps attach behind the fulcrum, meaning that a triceps extension uses a first class lever. moved, can be increased without an increase in effort.

Second Class Levers In a second class lever, the load is located between the effort and the fulcrum. If the load is closer to the fulcrum than the effort, then less effort will be required to move the load. If the load is closer to the effort than the fulcrum, then more effort will be required to move the load.

In a third class lever, the effort is between the load and the fulcrum. Some examples of third class levers include fishing rods, cricket bats and chopsticks. Third class levers are different from first and second class levers because instead of force multipliers, they are speed multipliers.

The last domino hits a class one lever that has a string connected to it and a piece of cardboard. The domino makes it so the lever falls down, and cardboard goes with it. A mass is attached to the cardboard, and gravity allows to slide down a zipline.