580 likes | 652 Views
Forging new generations of engineers. Simple Machines. Simple Machines. Simple Machine: A device for overcoming resistance at one point by applying force at some other point. Work : The force applied on an object multiplied by the distance traveled by the object.
E N D
Simple Machine: A device for overcoming resistance at one point by applying force at some other point.
Work : The force applied on an object multiplied by the distance traveled by the object.
Effort : The force needed by a machine in order to accomplish work on a load.
Mechanical Advantage (MA) : The ratio of the output force (acting on a load) produced by a machine to the applied effort (the input force).
The Six Simple Machines • Inclined Plane • Wedge • Screw • Lever • Wheel and Axle • Pulley
The Six Simple Machines • Two general classes of simple machines. • Those that operate in straight lines or vectors. • Inclined Plane • Wedge • Screw • Those that operate by turning. • Lever • Pulley • Wheel and Axle
Inclined Plane 3 ft. 1 ft. This inclined plane has a mechanical advantage of 3. Mechanical Advantage = Length / Height MA = Length (3 ft.) divided by the height of the incline (1 ft.). 3 / 1 = 3 MA = 3
Inclined Plane 3 lb 1ft. Force x Distance = Work 3 lb of force x 1 ft or distance = 3 ft-lb work
Inclined Plane 3 ft. 1 lb 1 ft. By using in inclined plane with a mechanical advantage of 3 the amount of force required is reduced to one pound.
Inclined Plane EXAMPLES
Wedge A wedge is a movable inclined plane.
Wedge 3 ft. 1 ft. Mechanical Advantage = Length / Width MA = 3/1 MA = 3
4 in. Wedge 50 lb If the wedge to the right is pushed downward 12 in. with a 50 lb force the result would be a force on the material it is driven into of three times that or 150 lb. over one-third of the distance, 4 in. 150 lb 150 lb 12 in.
Wedge EXAMPLES
Screw 3 ft. 1 ft. A screw is basically an inclined plane wrapped around a cylinder.
Screw EXAMPLES
Lever Effort Load 3 lb Fulcrum A lever is a bar that pivots about a point called the fulcrum.
Lever 1 ft. 3 ft. MA=Fulcrum to Effort / Fulcrum to Load MA=3 / 1 MA=3
Lever 1 lb Effort Load 3 lb
Lever 1 lb Effort Load 3 lb Load Work = 3 lb x 1 ft = 3 ft lb Effort Work = 1 lb x 3 ft = 3 ft lb
Lever 1 lb Effort Load 3 lb Load Work = 3 lb x 1 ft = 3 ft lb Effort Work = 1 lb x 3 ft = 3 ft lb
Lever 1 lb Effort Load 3 lb Load Work = 3 lb x 1 ft = 3 ft lb Effort Work = 1 lb x 3 ft = 3 ft lb
Types of Levers Effort Load Fulcrum First Class Effort and Load on opposite sides of the Fulcrum
Effort Load Types of Levers Fulcrum First Class Effort and Load on opposite sides of the Fulcrum
Types of Levers First Class = See Saw
Types of Levers Effort Load Fulcrum Second Class Effort and Fulcrum on opposite side of the Load
Types of Levers 1 lb Effort Load 4 lb Fulcrum Second Class Effort and Fulcrum on opposite side of the Load
Types of Levers 1 lb Effort Load 4 lb Fulcrum Second Class Effort and Fulcrum on opposite side of the Load
Types of Levers Effort Load Fulcrum Second Class Effort and Fulcrum on opposite side of the Load
Types of Levers Effort Load Fulcrum Third Class Fulcrum and Load on opposite side of the Effort
Effort Load Types of Levers 4 lb 1 lb Fulcrum Third Class Fulcrum and Load on opposite side of the Effort
Types of Levers Load 1 lb 4 lb Effort Fulcrum Third Class Fulcrum and Load on opposite side of the Effort
Types of Levers Effort Load Fulcrum Third Class Fulcrum and Load on opposite side of the Effort
Lever EXAMPLES
Load 6 lb Wheel and Axle Effort
Load 6 lb Wheel and Axle Effort
Load 6 lb Wheel and Axle Effort
Load 6 lb Wheel and Axle MA=Wheel Diameter / Axle Diameter MA=6 / 1 MA= 6 Effort
Load 6 lb Wheel and Axle 1 lb Effort
Wheel and Axle EXAMPLES
Load 3 lb Pulley 3 lb Effort
Load 3 lb Pulley 1 3 lb Effort
Load 3 lb Pulley 3 lb Effort
Pulley 2 1 Effort Start Start Load