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INCLINE PLANE FAMILY. Inclined planes multiply and redirect force. Incline Plane. produces a MA by increasing distance through which the force must move. Real World Examples: Ramp Playground slide Can you think of one?. Incline Plane. Calculating Mechanical Advantage
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INCLINE PLANE FAMILY Inclined planes multiply and redirect force
Incline Plane • produces a MA by increasing distance through which the force must move. • Real World Examples: • Ramp • Playground slide • Can you think of one?
Incline Plane • Calculating Mechanical Advantage • IMA= Length of slope Height • IMA = Fo/Fi Distance Force
IP: Question # 1 • Sam broke his hand while juggling bowling balls and cannot lift a thing! Sam is moving to Wagadugu and must put all of his belonging into storage. To get his stuff into the moving truck, Sam decides to set-up a simple machine. He uses a ramp with the length (slope) of 12.5 m to reach the back of the moving truck which is 5 m off the ground. Calculate the ideal mechanical advantage of Sam’s simple machine? (Can you guess where Wagadugu is?)
IP: Question #2 • You got roped into helping your parents' friend move. You are loading some pretty heavy boxes, but luckily they have a ramp on the back of the truck. The truck is 1.5 meters of the ground and the ramp is 6 meters long. What is the IMA of this ramp?
IP: Question #3 • A ramp with a mechanical advantage of 6 is used to move a 36 Newton load. What input force is needed to push the load up the ramp?
IP: Question #4 • Katrina moves a box full of box with a force of 500 Newtons up to height of 6 meters, using a ramp. How much work did Katrina do?
Wedge • similar in shape to an inclined plane • used as either separating or holding devices. • A difference between an inclined plane & wedge. • -An inclined plane remains stationary while the wedge moves.
Wedge • IMA = Slope of the Wedge Thickness • IMA = Fo/Fi
Wedge: Question # 1 • A door stop has a slope of 22 cm and a thickness of 4cm. Draw a diagram of the door stop (wedge) and label the slope and thickness. Calculate the ideal mechanical advantage.
Wedge: Question #2 • Blake used a wedge that exert an output force of 14 Newtons and had a MA of 4. What was the input force?
Mechanical Advantage • Inclined Plane • MA>1 • Wedge • MA>1
Screw • modified version of the inclined plane • think of threads of the screw as a type of circular ramp (or inclined plane). • screw is often turned by another simple machine such as a lever or a wheel and axle. • When a screw is turned once, it advances by the distance between adjacent screw threads. This distance is commonly called the "pitch”.
Screw • IMA = circumference/pitch • IMA = Fo/Fi • Calculating Total Distance • TD = Circumference of the screw× # of threads
Screw: Question # 1 • Wyatt uses a wooded screw to hold together the pieces of the chair he is making. If the radius of the screw is 2 cm and the pitch of the screw is 0.55 cm, then what is the mechanical advantage of the screw?
Screw: Question #2 • George watches Wyatt build his chair. From all of his calculations, George believes that Wyatt has done 50J of work placing together one part of the chair. If George measures Wyatt’s input force to be 200 Newtons, then what be the distance that the screw travelled?
Screw: Question #3 • If the circumference of a screw is 3 millimeters and the screw has 6 threads, then what is the total distance that the screw can travel?