grade 6 mrs. figoten work & simple machines work work = force force x distance joules joules =...

GRADE 6GRADE 6GRADE 6GRADE 6Mrs. Mrs. FigotenFigoten

WORK & SIMPLEWORK & SIMPLE MACHINES MACHINES

WORKWORK = = FORCEFORCE X X DISTANCEDISTANCE

JoulesJoules = = newtons (N) newtons (N) X X meters (m)meters (m)

WorkWork done done = = FForce x orce x DDistance movedistance moved = 30 = 30 newtonsnewtons (F)(F) x 8 x 8 metersmeters (D)(D) = 240 = 240 JoulesJoules

Because the block is held up high, it Because the block is held up high, it becomes: becomes: potentialpotential energy energy = 240= 240 JJ (due to gravity(due to gravity)

If the mass then falls freely to the ground,If the mass then falls freely to the ground, just before it hits the ground, it’s just before it hits the ground, it’s . . . . . .

240240 JJ of of kinetickinetic energy energy

CALCULATING WORKCALCULATING WORKThe crane uses 30 newtons of force to lift the iron block 8 meters.The crane uses 30 newtons of force to lift the iron block 8 meters.

----------------------------------------------------------------------------------------------How much work was done?How much work was done?

INCLINED PLANEINCLINED PLANE Flat surface with 1 end higher than otherFlat surface with 1 end higher than other

Used to gradually raise or lower objectsUsed to gradually raise or lower objects

EFFICIENCYEFFICIENCY Friction reduced if surfacesFriction reduced if surfaces

of plane & load are smooth of plane & load are smooth

MECHANICAL ADVANTAGEMECHANICAL ADVANTAGE (MA) (MA)

INPUTINPUT FORCE FORCE DISTANCEDISTANCE

Longer PlaneLonger Plane = More Distance = More Distance

Examples ofExamples ofINCLINED INCLINED PLANESPLANES

http://www.smartown.com/sp2000/machines2000/inclinedplane.htm

WEDGEWEDGE Type of inclined planeType of inclined plane Has 1 or 2 sloping sidesHas 1 or 2 sloping sides Force applied to wide endForce applied to wide end Narrow end driven into object– push object Narrow end driven into object– push object

apartapart

EFFICIENCYEFFICIENCY Friction reduced if edge sharperFriction reduced if edge sharper

MECHANICAL ADVANTAGEMECHANICAL ADVANTAGE (MA)(MA)


Longer Point/EdgeLonger Point/Edge = More Distance = More Distance

Examples of WEDGES

SCREWSCREW Type of inclined planeType of inclined plane

Wrapped around a rodWrapped around a rod Direction of force changedDirection of force changed Amount of force increasedAmount of force increased

EFFICIENCYEFFICIENCY Increased when threads closerIncreased when threads closer



More threadsMore threads = More Distance = More Distance

Examples ofSCREWS

LEVER Does work by turning around

FULCRUM (fixed point) Force applied to do the work =

EFFORT Force created by LOAD when trying

to move it = RESISTANCE

EFFICIENCY GREATESTWHEN WORK REQUIRESTHE LEAST EFFORT

MECHANICAL ADVANTAGE (MA)MECHANICAL ADVANTAGE (MA)


Longer Effort ArmLonger Effort Arm = More Distance = More Distance

loadload

efforteffort

fulcrumfulcrum

effort arm

effort arm

LESS EFFORT NEEDEDTO DO THE WORK

LESS DISTANCE BETWEEN

LOAD & FULCRUM

TYPES OF LEVERS

FIRST CLASS LEVER

SECOND CLASS LEVER

THIRD CLASS LEVER

Summary of LEVER CLASSES

1st Class 2nd Class 3rd Class

Fulcrum= Pivot Point

Effort force = input force

Load (Resistance) = output

force

By whether the fulcrum, load, or effort is in the center.

How do you know what class a lever is?

WHEEL & AXLE Large wheel fixed to smaller wheel (or shaft)

called an axle

Both turn together

Effort usually on larger wheel, moving load of axle



Turning Turning larger wheellarger wheel = More Distance = More Distance

Think of as lever Think of as lever rotating in circlerotating in circle around center fulcrumaround center fulcrumLike steering wheel (larger wheel) on

column (axle)Wheel & axle turn together

EFFICIENCY:EFFICIENCY: Reduced friction with lubricant

HOW DOES WHEEL & AXLE WORK?

PULLEYWheel with groove Allows rope to ride on wheel

without slipping off



Rope around Rope around more wheelsmore wheels = More Distance = More Distance

TYPES OF PULLEYS

FIXED PULLEY (like clothesline or flagpole)

Pulley stays in one position

Moves LOAD up, down or sideways

Changes DIRECTION of force

Does not reduce EFFORT

TYPES OF PULLEYS

MOVABLE PULLEY(for lifting or lowering heavy objects)

Moves along with LOAD

Reduces EFFORT

Increases DISTANCE

Examples ofPULLEYS

GEARS

Wheels with teeth, so one turns the next SMALLER gear turns FASTER than larger gear One gear makes other gear beside it turn in

OPPOSITE DIRECTION Speeds things up,slows them down, changes

direction of force

COMPOUND MACHINE

Compound machines are made of 2 or more

simple machines.

KIDS’ INVENTIONS

Illustrating… COMPOUND MACHINES Made of

at Least 2 SIMPLE MACHINES

He can clean your room. It can take the trash out and do other chores. He is made of gears, screws and pulleys..

This is the Chore 3,000.

Our simple machine does a lot of stuff such as recycles cans and then washes them, and then has them come to be used again. Another thing it does is washes clothes and hangs them back up for kids.

It also cooks popcorn and pours drinks.Another thing it does is dusting, itwill dust anything for you. The simplemachines we used were the wheeland axle,inclined plane, just wheels,pulleys, and gears.

This simple machine is The Kids’ Chore.

He can clean your room. It can take the trash out and do other chores. He is made of gears, screws and pulleys.

This is the Chore 5,000.

grade 6 mrs. figoten work & simple machines work work = force force x distance joules joules =...

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