Simple Machines make work easier no less force

Simple Machines - make work easier no less force - one of the six basic types of machines levers wheel and axle inclined plane wedge screw pulley

Levers Definition - a rigid bar that is free to move around a fixed point - all levers have a rigid arm that turns around a fixed point called the fulcrum - force is transferred from one part of the arm to another - original input force can be multiplied or redirected into output force - levers are divided into 3 classes, based on the locations of the input force, output force, and the fulcrum

Lever Family Cont. Input force First class - fulcrum is in the middle of an arm - the input force acts on one end - the other end applies an output force - MA can be: <1, >1, =1 depending on the positioning of the fulcrum ex. teeter totter, scissors, tongs Output force

Levers output force Input force Second class - fulcrum is at one end of the arm - input force is applied to the other end - output force is in the middle - MA will always > 1 ex. wheel barrow

Lever Family Cont. input force Third class - input force is in the middle - output force is one end - fulcrum is on the other end - multiplies distance rather than force - MA always < 1 ex. baseball bats, hockey sticks, golf clubs, broom Output force

Wheel and Axle n - - Definition - simple machine that consists of two disks or cylinders, each one with a different radius ex. steering wheel, screwdriver small input force, multiplied to become a large output force MA >1 or =1

Inclined Planes Definition - slanted surface along which a force moves an object to a different elevation ex. knife, ax, zipper, wedge, screw - ramp redirects the force applied to lift object upward - turns a small input force into a large output force by spreading the work out over a large distance - wedge: functions as two inclined planes back to back, turning a downward force into two forces directed out to the sides -screw: an inclined plane wrapped around a cylinder

Pulleys Definition - a simple machine that consists of a rope that fits into a groove in a wheel. - can change size, direction of input force or both 3 Types of Pulleys - fixed pulleys - moveable pulleys - pulley system

Types of Pulleys - fixed pulleys: changes the - direction of the input force - moveable pulleys: changes both - the direction and the size - of the input force - pulley system: made of both fixed and moveable pulleys

Compound Machines Definition - a machine that is made of more than one simple machine ex. scissors, jacks, bicycle, washing machine, _car, clock

Practice Question #1 A simple Machine multiplies your ________.

Practice Question #2 A simple machine has an input force of 9 Newtons and can lift 90 Netwons. What is the mechanical advantage? n n n A. 180 B. 10 C. 99

Practice Question #3 Which lever has the least mechanical advantage?

Practice Question #4 A lever has a resistance distance of 6 cm and an effort distance of 60 cm. What is the mechanical advantage? n n n A. 10 B. 360 C. 0. 1

Practice Question #5 Which of the following is NOT a simple machine? n n A. wheel and axle B. Generator C. Lever D. Bulley

Practice Question #6 A machine helps you feel like you are putting less effort in because it allows you to trade distance for ______.

Practice Question #7 True or false? A screw is a type of inclined plane.

Practice Question #8 What is the following simple machine?

Practice Question #9 What is the mechanical advantage of a ramp that is 10 m long and rises 2 meters?

Practice Question #10 What is the type of lever that is used to gain a distance advantage? Give an example of this type of lever.