The wedge is two inclined planes back to back. They are used to lift, cut or separate items. Examples of the wedge are: a knife, a door stop , a log splitter, and an ax.
Beside above, is a ramp a wedge? The Wedge ramp It is thick on one end and tapers to a thin or sharp edge on the other end. Technically it is an inclined plane or two inclined planes put together to form a triangle that moves.
A wedge turns a single downward force into two forces directed out to the sides. It both multiplies force and changes the direction of the force. A wedge is a moving inclined plane. A screw is an inclined plane wrapped around a cylinder. Just like all simple machines, an inclined plane makes work easier. A wedge looks like two inclined planes stuck together. The edge of a wedge is often called the blade. The big difference between a wedge and an inclined plane is that, while the inclined plane stays still, a wedge moves to do its work.
Is a fork a wedge? A wedge is really an inclined plane turned on its side. But instead of helping you move things to a higher level, a wedge helps you push things apart. The blades of a knife or a shovel are both wedges. A wedge can also be round, like the tip of a nail, or the tines on your fork.
Is a broom a wedge? They are a lever, pulleys, inclined plain, wheel and axle, screw, and wedge. The lever is used very often an example of a lever is a broom. Your hand is the fulcrum and when you sweep it is a lever. A wedge is a inclined plain with one or two sloping sides. Although engineers use each of these three simple machines for different purposes, they all operate on the same mechanical principles. Before we go any farther, we need a brief review of the essential principles about simple machines which will prove especially helpful when studying each individual machine.
The most important fact is that simple machines never change the amount of work done, only the way in which work is done. Let's look at the definition of work, which is defined to be the product of force and distance and written mathematically as:. Since the amount of work to be done does not change for a particular chore, this value remains constant. However, both force and distance can in fact be altered.
Simple machines often accomplish work differently by applying the input force, or effort, over a greater distance in order to make work easier to carry out. That is, in order to reduce the amount of force required to do the work, the distance must be proportionately increased. For example, let's say Emma the engineer needs to do 20 Joules worth of work. She can accomplish this in many different ways, one of which is to exert a force of 20 Newtons over a distance of 1 meter.
However, an easier method may involve the application of a mere 2 Newton force over a distance of 10 meters. In either case, Emma does the same amount of work; however, it is much easier for her to accomplish this by applying less force over a further distance. Figure 2 illustrates how the same amount of work can be accomplished in many different ways, although some ways are easier — or more efficient — than others.
This is the case when using a machine. Figure 2. Equations showing the different ways to achieve the same amount of work. The inclined plane see Figure 3 is perhaps the oldest and most rudimentary simple machine known to engineers. In fact, many of you are probably wondering how a slanted surface could possibly be classified as a "machine. Figure 3. The inclined plane. The key idea here is that less effort is needed if a load is transferred over a long ramp or inclined path, as opposed to lifting it directly over a vertical path.
For example, you may have noticed how movers move very heavy objects, such as a piano, into the back of their moving truck. Obviously, they cannot easily lift such a heavy piece of furniture directly up and into the back of their truck. Instead, they use a long ramp — or inclined plane — to complete the job. This idea was used long ago by the ancient Egyptians: they used the inclined plane and human strength to erect monumental structures to amazing heights.
Even today, engineers employ the inclined plane in many other applications in order to accomplish seemingly impossible tasks. Just a few of these examples include wheelchair ramps, escalators, stairs, highways and even hiking trails, which all rely on the inclined plane as a means of raising heavy objects more easily. In addition to lifting heavy objects, engineers are also interested in splitting or separating material with as little effort as possible. In this case engineers employ the use of a wedge so that tasks such as chopping firewood, cutting paper, and mowing our yards are made much easier.
The wedge, as illustrated in Figure 4, is a simple machine often considered to be a slight variation of the inclined plane since it really consists of two inclined planes set back to back.
As a result, one end is thicker than the other so that a sharp cutting edge is formed. Figure 4. The wedge. While it is true that the wedge is very similar to the inclined plane physically, engineers use this machine for slightly different purposes. The inclined plane functions to transport heavy objects over a stationary surface, while the wedge itself can move in order to move or lift objects. Therefore, the wedge is essentially an inclined plane in motion. When a wedge is moved, a forward force is converted into the outward or parting force used to separate or split material.
Even though the wedge can also be used to lift or move objects a short distance, throughout history it has been primarily utilized as a valuable cutting device. An axe is a classic example of how a wedge is used to make work easier. Can you imagine how hard it would be to cut down a tree or chop wood without an axe? Even the strongest of men pulling on a piece of timber in opposite directions could not complete the chore. Yet, generally one hefty swing of an axe will accomplish the feat with little effort.
In addition to the axe, other familiar tools such as a knife, shovel, plow and scissors all take advantage of the wedge in order to easily separate bound material.
Can you think of other devices where the wedge is at work? Sometimes it is difficult to identify the wedge in the various engineering designs today because of the many different appearances it can have.
It is interesting, however, when we realize where the wedge can be found in as many unfamiliar places as well, such as the hull of a ship, airplane wings, and even our front teeth! While all six simple machines have their own distinct qualities, only the screw is able to convert a rotational force into a favorable linear force. This characteristic is desirable in many engineering applications where rotational motion is the only source of effort available to perform work, like a jet engine.
Similar to the wedge, the screw see Figure 5 is also closely related to the inclined plane since it is actually composed of an inclined plane wrapped around a cylinder. The spiraled edges around the cylindrical surface, commonly referred to as the screw threads, give the screw its ability to do work. Figure 5. The screw. Since engineers can apply this machine to two different unrelated applications, the screw has two general classifications: the fastening screw and the lifting screw.
In contrast to the wedge, which is designed with the ability to cut and separate material, the fastening screw is used to fasten and join two pieces of material together. This type of screw usually has sharp threads which cut into the parts being joined together.
The materials eventually become squeezed and held together between the head of the screw and its threads. Friction from the rough threads, on the other hand, keeps the screw from working loose over time. The lifting screw is the other type of screw, designed primarily for lifting or moving mass in a direction parallel to the axis of the screw.
Since the lifting screw must rotate many times in order to advance the load a short distance, work is made easier with its help. Although it may be hard to visualize, a great example of the lifting screw is a common propeller found on a small aircraft or boat.
When the propeller is spun by a rotational force provided by the engine, a linear force is created along its rotational axis to produce thrust. Aeronautical engineers have also found this tool to be exceptionally beneficial for helicopter rotors and jet engines as well. In addition to the propeller, a spiral staircase, nut and bolt, woodscrew, auger, drill bit, worm gear, and windmill are also good examples of how the screw is applied in many helpful engineering systems today.
It is well known that simple machines can make work easier, but exactly how much easier? The answer to this question is known as mechanical advantage, which is defined to characterize a machine's ability to lessen the burden of work.
Mechanical advantage is the number of times a force exerted on a machine is multiplied by the machine, in other words, the degree to which a machine makes work easier. Recall from Lesson 1 that the mechanical advantage of all machines is defined by the general expression:. With the addition of friction opposing the movement of the mass, the mechanical advantage is reduced as some of the input energy is converted to heat.
As a result, more effort is required in order to push the object up the inclined plane. A wedge is a simple machine that is made up of two inclined planes forming a triangular shape. It provides mechanical advantage by converting the force applied at its end into forces perpendicular to the inclined surfaces. As such, a wedge is a good tool to cut objects for example, an axe , hold objects in place for example, a doorstopper , and lift objects in order to separate them from the surface they are resting on.
Similar to an inclined plane, the mechanical advantage for a wedge is the ratio of the length of its slope to its height:. In the following example, for the sake of simplicity, the coefficient of friction is assumed to be independent of whether or not the object is in motion.
Use the sliders to adjust the appropriate parameters. The magnitude and directions of the forces acting on the box are represented by vectors in the diagram. Weight F g :. Applied force F a. More MathApps. Download Help Document. Online Help. All Products Maple MapleSim. Inclined Planes and Wedges Main Concept Mechanical advantage Mechanical advantage is a measure of the force amplification achieved by using a tool, mechanical device or machine system.
Inclined Planes An inclined plane is a simple machine that provides mechanical advantage by reducing the force required to lift an object.
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