More Simple Machine Flashcards
First class lever example and discerption
Pliers are an example of a First Class lever. Levers of the first class increase force and reverse direction. On one end you have the handle which is the Effort side (E), and on the opposite end you have the jaws or the Resistance side (R). The fulcrum is between these two points, closer to the jaws “Resistance end”. The Resistance Distance (RD) is from the end of the jaws back to the fulcrum. The Effort Distance (ED) is from the end of the handle back to the fulcrum.
Third class lever and description
A fishing rod is an example of a Third Class lever. Levers of the third class multiply speed or distance rather than force. The fulcrum is located on one end at the handle and the load or Resistance (R) is located on the opposite end. The Effort (E) is located in between both near the fulcrum. The Resistance Distance (RD) runs the length of the pole and the Effort Distance (ED) runs from the effort point back to the fulcrum.
Second class lever and description
A wheelbarrow is an example of a Second Class lever. Levers of the second class multiply force, and their direction is always the same. The pivot point or fulcrum is located on one end at the wheel. The Effort (E) is located on the opposite end, with the Load or Resistance (R) located in between nearer to the fulcrum. The Resistance Distance (RD) begins at the load and ends at the fulcrum. The Effort Distance (ED) runs the entire length of this lever.
Incline plane example and description
An example of an inclined plane is a ramp. A ramp is shaped like a right triangle. The (RD) is the height, and the (ED) is the slope or hypotenuse. The (E) is the push or pull, and the (R) is the load.
Wedge example and description
An example of a wedge is a rubber door stop. The wedge is also shaped similar to a right triangle. The (ED) is adjacent side of the right angle. The (RD) is the height of the wedge under the resistance. The (R) moves along the slope or hypotenuse, and the (E) moves parallel with the slope.
Screw example and description
An example of a screw is a screw on a jack. A screw is a combination of the inclied plane, the wedge, and the wheel and axle. It is used to transmit motion, apply tremendous force, hold parts together, and obtain measurements. The number of threads per inch or pitch is the (RD), the (ED) is the circumfrence of the handle used to apply force. The (E) is the force applied, and the (R) is the load.
Describe the wheel and axle
Sometimes called a “continuous lever” serves one of the two basic functions of transmitting force or producing a change in speed. Cannot have an increase in speed and force, the relationship is inversely proportional. ED is the distance from the center of the wheel or axle that the E or force is being applied. The RD is the distance from the center of the wheel or axle that the load or R is being raised. EX: Screwdriver, chain hoist, speed handle.
Describe the pulley
Is a wheel that rigidly fastened to a shaft on which it turns and transmits either to or from the shaft. Pulleys are generally used in pairs. There are fixed and movable pulleys, when several pulleys are used together it is called a block and tackle. EX: Crane block and tackle hooks