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50-495: A ramp , or inclined plane, is a simple machine. Ramp may also refer to: Ramp An inclined plane , also known as a ramp , is a flat supporting surface tilted at an angle from the vertical direction , with one end higher than the other, used as an aid for raising or lowering a load. The inclined plane is one of the six classical simple machines defined by Renaissance scientists. Inclined planes are used to move heavy loads over vertical obstacles. Examples vary from

100-658: A dyke that keeps two bodies of water apart, such as bodies with a different water level on each side, or with salt water on one side and fresh water on the other. This may also be the primary purpose of a structure, the road providing a hardened crest for the dike, slowing erosion in the event of an overflow. It also provides access for maintenance as well perhaps, as a public service. Notable causeways include those that connect Singapore and Malaysia (the Johor-Singapore Causeway ), Bahrain and Saudi Arabia (25-km long King Fahd Causeway ) and Venice to

150-553: A much higher bridge (or part of a single bridge) in the middle so that taller boats may pass underneath safely. Causeways are most often used to connect the barrier islands with the mainland . In the case of the Courtney Campbell Causeway , however, the mainland ( Hillsborough County ) is connected by a causeway to a peninsula ( Pinellas County ). A well-known causeway is the NASA Causeway connecting

200-484: A path. The name by this route came to be applied to any firmly surfaced road. It is now little-used except in dialect and in the names of roads which were originally notable for their solidly made surface. The 1911 Encyclopædia Britannica states: "causey, a mound or dam, which is derived, through the Norman-French caucie (cf. modern chaussée ), from the late Latin via calciata , a road stamped firm with

250-556: A paved ramp 6 km (3.7 miles) long, the Diolkos , to drag ships overland across the Isthmus of Corinth . However the inclined plane was the last of the six classic simple machines to be recognised as a machine. This is probably because it is a passive and motionless device (the load is the moving part), and also because it is found in nature in the form of slopes and hills. Although they understood its use in lifting heavy objects,

300-405: A ramp used to load goods into a truck, to a person walking up a pedestrian ramp, to an automobile or railroad train climbing a grade. Moving an object up an inclined plane requires less force than lifting it straight up, at a cost of an increase in the distance moved. The mechanical advantage of an inclined plane, the factor by which the force is reduced, is equal to the ratio of the length of

350-527: A short stretch of viaduct is called an overpass . The distinction between the terms causeway and viaduct becomes blurred when flood-relief culverts are incorporated, though generally a causeway refers to a roadway supported mostly by earth or stone, while a bridge supports a roadway between piers (which may be embedded in embankments). Some low causeways across shore waters become inaccessible when covered at high tide . The Aztec city-state of Tenochtitlan had causeways supporting roads and aqueducts. One of

400-481: A vertical distance by using the normal force of the plane to reduce the gravitational force . Aircraft evacuation slides allow people to rapidly and safely reach the ground from the height of a passenger airliner . Other inclined planes are built into permanent structures. Roads for vehicles and railroads have inclined planes in the form of gradual slopes, ramps, and causeways to allow vehicles to surmount vertical obstacles such as hills without losing traction on

450-515: A word derived not from trampling but from ramming or tamping. The Welsh word cawsai translates directly to the English word 'causeway'; it is possible that, with Welsh being a lineal linguistic descendant of the original native British tongues, the English word derives from the Welsh. A transport corridor that is carried instead on a series of arches, perhaps approaching a bridge, is a viaduct ;

500-409: Is H = 1 meter and its length is L = 5 meters, then the mechanical advantage is which means that a 20 lb force will lift a 100 lb load. The Liverpool Minard inclined plane has the dimensions 1804 meters by 37.50 meters, which provides a mechanical advantage of so a 100 lb tension force on the cable will lift a 4810 lb load. The grade of this incline is 2%, which means the angle θ

550-477: Is a high priority for local, regional, and even national authorities. Causeways can separate populations of wildlife, putting further pressure on endangered species . Causeways can cause a mineral imbalance between portions of a body of water. For example, a causeway built in the Great Salt Lake has caused the northern half of the lake to have much higher salinity, to the point that the two halves show

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600-399: Is dissipated as heat by friction, W fric {\displaystyle W_{\text{fric}}} , so less work is done on the load. Due to conservation of energy , the sum of the output work and the frictional energy losses is equal to the input work Therefore, more input force is required, and the mechanical advantage is lower, than if friction were not present. With friction,

650-481: Is small enough that sin θ≈tan θ. Causeway When first used, the word causeway appeared in a form such as "causey way", making clear its derivation from the earlier form "causey". This word seems to have come from the same source by two different routes. It derives ultimately, from the Latin for heel, calx , and most likely comes from the trampling technique to consolidate earthworks . Originally,

700-488: Is sometimes called ideal mechanical advantage I M A {\displaystyle \mathrm {IMA} } while the MA when friction is included is called the actual mechanical advantage A M A {\displaystyle \mathrm {AMA} } . If there is no friction between the object being moved and the plane, the device is called an ideal inclined plane . This condition might be approached if

750-422: Is the coefficient of static friction between the two surfaces, which varies with the material. When no input force is applied, if the inclination angle θ {\displaystyle \theta } of the plane is less than some maximum value ϕ {\displaystyle \phi } the component of gravitational force parallel to the plane will be too small to overcome friction, and

800-403: Is the force needed to hold the load motionless on the inclined plane, or push it up at a constant velocity. If the input force is greater than this, the load will accelerate up the plane. If the force is less, it will accelerate down the plane. Where there is friction between the plane and the load, as for example with a heavy box being slid up a ramp, some of the work applied by the input force

850-408: Is the maximum angle at which a load can rest motionless on an inclined plane due to friction without sliding down. This angle is equal to the arctangent of the coefficient of static friction μ s between the surfaces. Two other simple machines are often considered to be derived from the inclined plane. The wedge can be considered a moving inclined plane or two inclined planes connected at

900-703: Is the most well-known, because of its originality and use of a string of beads (see box). In 1600, Italian scientist Galileo Galilei included the inclined plane in his analysis of simple machines in Le Meccaniche ("On Mechanics"), showing its underlying similarity to the other machines as a force amplifier. The first elementary rules of sliding friction on an inclined plane were discovered by Leonardo da Vinci (1452-1519), but remained unpublished in his notebooks. They were rediscovered by Guillaume Amontons (1699) and were further developed by Charles-Augustin de Coulomb (1785). Leonhard Euler (1750) showed that

950-424: Is zero. Since the direction of the frictional force is opposite for the case of uphill and downhill motion, these two cases must be considered separately: The mechanical advantage of an inclined plane is the ratio of the weight of the load on the ramp to the force required to pull it up the ramp. If energy is not dissipated or stored in the movement of the load, then this mechanical advantage can be computed from

1000-414: The ancient Greek philosophers who defined the other five simple machines did not include the inclined plane as a machine. This view persisted among a few later scientists; as late as 1826 Karl von Langsdorf wrote that an inclined plane " ...is no more a machine than is the slope of a mountain ". The problem of calculating the force required to push a weight up an inclined plane (its mechanical advantage)

1050-503: The tangent of the angle of repose on an inclined plane is equal to the coefficient of friction . The mechanical advantage of an inclined plane depends on its slope , meaning its gradient or steepness. The smaller the slope, the larger the mechanical advantage, and the smaller the force needed to raise a given weight. A plane's slope s is equal to the difference in height between its two ends, or " rise ", divided by its horizontal length, or " run ". It can also be expressed by

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1100-598: The Romans are examples of early inclined planes that have survived, and show that they understood the value of this device for moving things uphill. The heavy stones used in ancient stone structures such as Stonehenge are believed to have been moved and set in place using inclined planes made of earth, although it is hard to find evidence of such temporary building ramps. The Egyptian pyramids were constructed using inclined planes, Siege ramps enabled ancient armies to surmount fortress walls. The ancient Greeks constructed

1150-410: The angle the plane makes with the horizontal, θ {\displaystyle \theta } . The mechanical advantage M A {\displaystyle \mathrm {MA} } of a simple machine as defined as the ratio of the output force exerted on the load to the input force applied.The inclined plane the output load force is just the gravitational force of the load object on

1200-481: The base. The screw consists of a narrow inclined plane wrapped around a cylinder . The term may also refer to a specific implementation; a straight ramp cut into a steep hillside for transporting goods up and down the hill. This may include cars on rails or pulled up by a cable system; a funicular or cable railway , such as the Johnstown Inclined Plane . Inclined planes are widely used in

1250-720: The cobbles together. However, some of the stones were left loose. In Scotland , the skirmish known as Clense the Calsey, or Cleanse the Causeway , took place in the High Street of Edinburgh in 1520. In the 18th century, Dahomey lacked an effective navy hence it built causeways for naval purposes starting in 1774. The modern embankment may be constructed within a cofferdam : two parallel steel sheet pile or concrete retaining walls , anchored to each other with steel cables or rods. This construction may also serve as

1300-465: The conservation of energy equation above and rearranging To express the mechanical advantage by the angle θ {\displaystyle \theta } of the plane, it can be seen from the diagram (above) that So So the mechanical advantage of a frictionless inclined plane is equal to the reciprocal of the sine of the slope angle. The input force F i {\displaystyle F_{\rm {i}}} from this equation

1350-404: The construction of a causeway used earth that had been trodden upon to compact and harden it as much as possible, one layer at a time, often by slaves or flocks of sheep . Today, this work is done by machines. The same technique would have been used for road embankments, raised river banks, sea banks and fortification earthworks. The second derivation route is simply the hard, trodden surface of

1400-404: The dimensions of the ramp. In order to show this, let the position r of a rail car on along the ramp with an angle, θ , above the horizontal be given by where R is the distance along the ramp. The velocity of the car up the ramp is now Because there are no losses, the power used by force F to move the load up the ramp equals the power out, which is the vertical lift of the weight W of

1450-458: The entrance of the Harbour made from blocks of reef and coral nearly a meter high. These acted as breakwaters , allowing mangroves to grow which is one of the ways the breakwater can be spotted from a distance. Some parts of the causeway are made from the bedrock, but usually the bedrock was used as a base. Coral stone was also used to build up the causeways, with sand and lime being used to cement

1500-453: The feet ( calcare , to tread)." The word is comparable in both meanings with the French chaussée , from a form of which it reached English by way of Norman French . The French adjective chaussée carries the meaning of having been given a hardened surface and is used to mean either paved or shod. As a noun chaussée is used on the one hand for a metalled carriageway, and on

1550-404: The force multiplied by the displacement an object moves. The work done on the load is equal to its weight multiplied by the vertical displacement it rises, which is the "rise" of the inclined plane The input work is equal to the force F i {\displaystyle F_{\text{i}}} on the object times the diagonal length of the inclined plane. Substituting these values into

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1600-482: The form of loading ramps to load and unload goods on trucks, ships and planes. Wheelchair ramps are used to allow people in wheelchairs to get over vertical obstacles without exceeding their strength. Escalators and slanted conveyor belts are also forms of an inclined plane. In a funicular or cable railway a railroad car is pulled up a steep inclined plane using cables. Inclined planes also allow heavy fragile objects, including humans, to be safely lowered down

1650-505: The hanging part of the chain need not be symmetrical because the hanging part need not retain its shape when let go. Even if the chain is released with a zero angular momentum, motion including oscillations is possible unless the chain is initially in its equilibrium configuration, a supposition which would make the argument circular. Inclined planes have been used by people since prehistoric times to move heavy objects. The sloping roads and causeways built by ancient civilizations such as

1700-522: The harbour, on the orders of Winston Churchill . The Estrada do Istmo connecting the islands of Taipa and Coloane in Macau was initially built as a causeway. The sea on both sides of the causeway then became shallower as a result of silting, and mangroves began to conquer the area. Later, land reclamation took place on both sides of the road and the area has subsequently been named Cotai and become home to several casino complexes. Various causeways in

1750-413: The load is stationary, neither sliding up or down the plane, whereas with a frictionless inclined plane there is only one particular value of input force for which the load is stationary. A load resting on an inclined plane, when considered as a free body has three forces acting on it: Using Newton's second law of motion the load will be stationary or in steady motion if the sum of the forces on it

1800-444: The load will only move if the net force parallel to the surface is greater than the frictional force F f {\displaystyle F_{\text{f}}} opposing it. The maximum friction force is given by where F n {\displaystyle F_{\text{n}}} is the normal force between the load and the plane, directed normal to the surface, and μ {\displaystyle \mu }

1850-492: The load will remain motionless. This angle is called the angle of repose and depends on the composition of the surfaces, but is independent of the load weight. It is shown below that the tangent of the angle of repose ϕ {\displaystyle \phi } is equal to μ {\displaystyle \mu } With friction, there is always some range of input force F i {\displaystyle F_{\text{i}}} for which

1900-400: The load. The input power pulling the car up the ramp is given by and the power out is Equate the power in to the power out to obtain the mechanical advantage as The mechanical advantage of an inclined plane can also be calculated from the ratio of length of the ramp L to its height H, because the sine of the angle of the ramp is given by therefore, Example: If the height of a ramp

1950-808: The mainland, all of which carry roadways and railways. In the Netherlands there are a number of prominent dikes which also double as causeways, including the Afsluitdijk , Brouwersdam , and Markerwaarddijk . In the Republic of Panama a causeway connects the islands of Perico, Flamenco, and Naos to Panama City on the mainland. It also serves as a breakwater for ships entering the Panama Canal . Causeways are also common in Florida , where low bridges may connect several human-made islands , often with

2000-399: The object is rolling like a barrel , or supported on wheels or casters . Due to conservation of energy , for a frictionless inclined plane the work done on the load lifting it, W out {\displaystyle W_{\text{out}}} , is equal to the work done by the input force, W in {\displaystyle W_{\text{in}}} Work is defined as

2050-634: The oldest engineered roads yet discovered is the Sweet Track in England . Built in 3807 or 3806 BC, the track was a walkway consisting mainly of planks of oak laid end-to-end, supported by crossed pegs of ash , oak, and lime , driven into the underlying peat. In East Africa , the Husuni Kubwa (the "Great Fort"), situated outside the town of Kilwa , was an early 14th-century sultan's palace and emporium that contained causeways and platforms at

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2100-421: The other for an embankment with or without a road. Other languages have a noun with similar dual meaning. In Welsh , it is sarn . The Welsh is relevant here, as it also has a verb sarnu , meaning to trample. The trampling and ramming technique for consolidating earthworks was used in fortifications and there is a comparable, outmoded form of wall construction technique, used in such work and known as pisé,

2150-409: The plane, its weight F w {\displaystyle F_{\text{w}}} . The input force is the force F i {\displaystyle F_{\text{i}}} exerted on the object, parallel to the plane, to move it up the plane. The mechanical advantage is The M A {\displaystyle \mathrm {MA} } of an ideal inclined plane without friction

2200-427: The road surface. Similarly, pedestrian paths and sidewalks have gentle ramps to limit their slope, to ensure that pedestrians can keep traction. Inclined planes are also used as entertainment for people to slide down in a controlled way, in playground slides , water slides , ski slopes and skateboard parks . As pointed out by Dijksterhuis, Stevin's argument is not completely tight. The forces exerted by

2250-413: The sloped surface to the height it spans. Owing to conservation of energy , the same amount of mechanical energy ( work ) is required to lift a given object by a given vertical distance , disregarding losses from friction , but the inclined plane allows the same work to be done with a smaller force exerted over a greater distance. The angle of friction , also sometimes called the angle of repose ,

2300-664: The town of Titusville on the Florida mainland to the rocket-launching facility at the Kennedy Space Center on Merritt Island . The Churchill Barriers in Orkney are some of the most notable sets of causeways in Europe. Constructed in waters up to 18 metres deep, the four barriers link five islands on the eastern side of the natural harbour at Scapa Flow . They were built during World War II as military defences for

2350-435: The winds and rains of approaching tropical storms —as well as waves generated by the storm in the surrounding bodies of water—make traversing causeways problematic at best and impossibly dangerous during the fiercest parts of the storms. For this reason (and related reasons, such as the need to minimize traffic jams on both the roads approaching the causeway and the causeway itself), emergency evacuation of island residents

2400-500: The world: Unlike tunnels or bridges, causeways do not permit shipping through the strait which can cause problems. In some cases, causeways were built with "gates" or other facilities to permit shipping to pass through. Causeways affect currents and may therefore be involved in beach erosion or changed deposition patterns; this effect has been a problem at the Hindenburgdamm in northern Germany. During hurricane seasons,

2450-443: Was apparently not communicated to other philosophers of the time. Girolamo Cardano (1570) proposed the incorrect solution that the input force is proportional to the angle of the plane. Then at the end of the 16th century, three correct solutions were published within ten years, by Michael Varro (1584), Simon Stevin (1586), and Galileo Galilei (1592). Although it was not the first, the derivation of Flemish engineer Simon Stevin

2500-486: Was attempted by Greek philosophers Heron of Alexandria (c. 10 - 60 CE) and Pappus of Alexandria (c. 290 - 350 CE), but their solutions were incorrect. It was not until the Renaissance that the inclined plane was solved mathematically and classed with the other simple machines. The first correct analysis of the inclined plane appeared in the work of 13th century author Jordanus de Nemore , however his solution

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