Presentation on theme: "GRADE 6 Mrs. Figoten WORK & SIMPLE MACHINES WORK WORK = FORCE FORCE X DISTANCE Joules Joules = newtons (N) X meters (m)"— Presentation transcript:
GRADE 6 Mrs. Figoten WORK & SIMPLE MACHINES
WORK WORK = FORCE FORCE X DISTANCE Joules Joules = newtons (N) X meters (m)
Work done = Force x Distance moved = Force x Distance moved = 30 newtons (F) x 8 meters (D) = 240 Joules = 240 Joules Because the block is held up high, it becomes: Because the block is held up high, it becomes: potential energy = 240 J (due to gravity = 240 J (due to gravity) If the mass then falls freely to the ground, just before it hits the ground, it’s J of kinetic energy CALCULATING WORK The crane uses 30 newtons of force to lift the iron block 8 meters How much work was done?
INCLINED PLANE Flat Flat surface with 1 end higher than other Used Used to gradually raise or lower objects EFFICIENCY Friction Friction reduced if surfaces of plane & load are smooth MECHANICAL ADVANTAGE (MA) MECHANICAL ADVANTAGE (MA) INPUT FORCE DISTANCE Longer Plane = More Distance
Examples of INCLINED PLANES
WEDGE Type Type of inclined plane Has Has 1 or 2 sloping sides Force Force applied to wide end Narrow Narrow end driven into object– push object apart EFFICIENCY Friction Friction reduced if edge sharper MECHANICAL ADVANTAGE (MA) INPUT FORCE DISTANCE Longer Point/Edge = More Distance
Examples of WEDGES
SCREW Type Type of inclined plane Wrapped Wrapped around a rod Direction Direction of force changed Amount Amount of force increased EFFICIENCY Increased Increased when threads closer MECHANICAL ADVANTAGE (MA) INPUT FORCE DISTANCE More threads = More Distance
Examples of SCREWS
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 GREATEST WHEN WORK REQUIRES THE LEAST EFFORT
MECHANICAL ADVANTAGE (MA) INPUT FORCE DISTANCE Longer Effort Arm = More Distance load effort fulcrum effort arm
LESS EFFORT NEEDED TO 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 MECHANICAL ADVANTAGE (MA) INPUT FORCE DISTANCE Turning larger wheel = More Distance
Think of as lever rotating in circle circle around center fulcrum Like steering wheel (larger wheel) on column (axle) Wheel & axle turn together EFFICIENCY: Reduced friction with lubricant
HOW DOES WHEEL & AXLE WORK?
PULLEY Wheel with groove Allows rope to ride on wheel without slipping off MECHANICAL ADVANTAGE (MA) INPUT FORCE DISTANCE Rope around more wheels = 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 of PULLEYS
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, it will dust anything for you. The simple machines we used were the wheel and 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.