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1 . Motion • Four types of motion: – LINEAR – Straight line, one direction – RECIPROCATING – straight line, back and forth – ROTATIONAL – Circular – OSCILLATING - Swinging
5 .Wheel & Axle
6 . Wheel and axle 1. The wheel is locked to a central axle so that when one is turned the other must turn 2. Longer motion at the edge of the wheel is converted to a shorter more powerful motion at the axle and vice versa http://www.sirinet.net/~jgjohnso/simple.html
7 .WHEEL AND AXEL • The axle is stuck rigidly to a large wheel. • Fan blades are attached to the wheel. • When the axel turns, the fan blades spin.
8 . Wheel and Axle • Wheel and axle is an example of a simple machine, that has two parts two it. • Unlike most simple machines, the parts have to work together, in order to move it. • Wheel and axle machines, has the axle attached to the wheel, to help it to move, and to speed up things.
9 . Wheel and Axel • The mechanical advantage of a wheel and axle is the ratio of the radius of the wheel to the radius of the axle. 1 5 • In the wheel and axle illustrated above, the radius of the wheel is five times larger than the radius of the axle. – Therefore, the mechanical advantage is 5:1 or 5. • The wheel and axle can also increase speed by applying the input force to the axle rather than a wheel. – This increase is computed like mechanical advantage. – This combination would increase the speed 5 times.
10 . Mechanical Advantages Con’t… • Mechanical advantages of wheel and axle is the ratio of the radius of the wheel, to the radius of the axle. • Here is an example of what I am talking about… The mechanical wheel advantage is- • Eel 5:1 or 5. The radius axle of the Note: wheel is 5 The radius is times equal to ½ larger the diameter of 1in 5in than the a circle radius of
11 . Wheel and Axle • The Wheel and Axle work off the same principle as the lever. Wheel diameter = 8 Axle diameter = 1 Produce an 8/1 MA
12 . Wheel and Axle • If the effort (input) is applied to the wheel, the axle is the resistance (output). – This will produce a mechanical advantage equal to the size ratio of the wheel as compared to the axle. Wheel diameter = 8 R E Axle diameter = 1 Produces an MA of 8 • What class lever is this wheel configuration?
13 . Wheel and Axle • If the effort (input) is applied to the axle, the wheel is the resistance (output). – This will create an increase in output distance but it will take more effort to turn. Wheel diameter = 8 E R Axle diameter = 1 Produces an MA of 1/8 • What class lever is this wheel configuration?
14 . Detailed Explanation on how it works… • Wheel and axle is a simple machine that is used to help move things, and the wheel and axle have to work together. • In order to use this machine, you need to have a force applied to either the axle or the wheel. • When the force is applied to the wheel, then the force is increased, the distance and speed are decreased. • when the force is applied to the axle, the force is decreased, the distance and speed are increased.
15 .General information of wheel and axle • It is a simple machine that consists of two circular objects, the wheel and the axle. • The axle is placed into the center or middle of the wheel, so that way it reduces the force that is needed to be applied, in order to move it. • It makes work easier by changing the amount on direction of the force applied to move the object. • The object that is being moved is a resistance(load) and the force applied to the outer edge of the wheel, is located at the axle.
16 . Mechanical Advantage…. Wheel and axle makes work easier by changing the amount of force applied to the load. Work is equaled to the amount of force applied to an object multiplied by the distance over which the force is applied, or in mathematical equation: work=force x distance. The Mechanical Advantage of a Wheel and Axle measures how much the machine multiplies the force applied by the user. There are two kinds of mechanical advantages, ideal and actual. The mechanical advantage equation is: MA=radius of the wheel divided by the radius of the axle. The mechanical advantage Efficiency =work output divided by work input times 100%, or in other words; Efficiency= actual MA/Ideal MA x100%
17 . Ideal/Actual Mechanical Advantages Ideal Mechanical Advantages ◦ Its the mechanical advantage of an ideal machine. It is usually calculated using physics principles because we have no ideal machine. It is also known as the theoretical mechanical advantages or IMA. ◦ IMA = DE / DR, where DE equals the effort distance and DR equals the resistance distance, is the formula used to find the ideal mechanical advantage of a machine . Actual Mechanical Advantages ◦ Its the mechanical advantage of a real machine. Actual mechanical advantage, or AMA, takes into consideration real world factors such as energy lost in friction, because of this way, it differs from the ideal mechanical advantage, to the efficiency. ◦ AMA = R / Eactual, Where, R is the resistance force, Eactual is the actual effort force, is the formula that you would used to calculate the actual mechanical advantage of a machine.
18 . Wheel and Axle Changes the Force The way that using the Wheel and Axle method changes the force, is depending on how big the wheel is compared to the axle. The smaller the wheel is, it gives you more speed, then what a bigger wheel would, because the bigger the wheel is, the further apart the force is around the wheel. When applying a force to a wheel and axle machine, make sure that the wheel is big enough for the force, so that way the axle will not snap, from to much force.
19 . Examples of Wheel and Axle
20 .IDENTIFY ITEMS THAT APPLY THE PRINCIPLE OF THE WHEEL AND AXLE IN THEIR OPERATION. GIVE AT LEAST TWO EXAMPLES FOR EACH CLASS.
21 . Wheel Examples (2nd Class) • Doorknob • Car Jack • Screwdriver • Telescope/ • Car Climate Controls Microscope Knobs • Dimmer Switch • Windmill/Wind • Pencil Sharpener Turbines • • Waterwheel Lamp Switch • • Wheel of Fortune Hamster Wheel • • The Price is Right Pottery Wheel
22 . Wheel Examples (3rd Class) • Ferris Wheel • Wheelbarrow • Carousel/Merry-Go- Round • Clock Hands • Pizza Cutter • Band Saw • Paint Roller • Circular Saw • Fan Blade • Blender/Grinder • Boat or Airplane • Bike/Car Tires Propeller • Fishing Reel • Helicopter Rotor • Big Wheel™
23 . Mechanical Transmission • A device which accomplishes one, or more, of the following: – Transfer motion from one point to another – Increase output speed OR force – Change direction of motion – Change type of motion
24 .penci l Cast door rolling p shar ers knobs In pene 2 3 4 r 1 rotar egg y dial beate Bicycle Fan telep r 7 8 hone 6 5 Wind roller record Wagon mill skate player 9 s 12 10 11
25 .Well that uses the wheel and axle method .
26 .A skate board is an example of a simple machine that uses the wheel and axle method.
27 .A wheel Barrel is 1 example of a compound Machine, because it uses the wheel and axle simple machine and it uses the lever simple machine.
28 .A manual can opener is another example of a compound machine because it uses three simple machines in it like the wheel and axle, which are the two wheels that rotate the lids, the two long arms that clamp the can securely make a simple machine called the lever, and the circular wheel that is sharpened, to cut the can lid is an example of a simple machine called a wedge.
29 .A Car uses the wheel and axle method for the steering wheel and the axle, or other wise known as the Dry Shift. It also uses lever for things like the gas/brake pedals, and emergency brake. Screws are found anywhere in the interior and the hood, and car also have pulleys in the engine drive belt, for the water pump, and the