Energy, Work and Simple Machines, Simple & Compound Machines, Examples of Simple Machines
lever arm
A beam, free to pivot on a point, used to move a load.
77 J
A lawnmower was pushed 70m with a force of 1.1N. How much work was done?
Energy
Ability to do work
Law of Conservation of Energy
Energy cannot be created or destroyed, only changed
Thermal energy
Energy equal to amount of heat within an object
Strain energy/elastic potential energy
Energy in anything stretched or bent, and capable of returning to original shape after release.
Kinetic energy
Energy of motion
Electrical Energy
Energy resulting from separation of electric charges.
2.8 N
How much force is showing on the spring scale?
210 J
It takes 70N of effort to lift a load 3m. How much work is done?
a lever(handle), a wheel and axle(wheels), or an inclined plane(bucket)
Name two simple machines that are in the compound machine above.
No, there isn't any distance involved
Scientifically, Is pushing against a wall work?
Energy Transformation
Takes place when energy changes from one form into another form.
Gravitational potential energy
The energy an object has because of its position within gravity field
Chemical (potential) Energy
The energy in food and fuel and cells
Newtons (N)
The metric term (SI) for measuring FORCE. (SI) means International System of Measurement
load
The weight or resistance that is moved using a simple machine.
force x distance
What two things do you need to know to be able to measure work?
mechanical advantage (it increases the effort)
What type of advantage do you get with this pulley?
directional advantage (you are pulling DOWN)
What type of advantage does this pulley system have?
fixed pulley, the pulley is "attached"
What type of pulley is shown here?
movable pulley
What type of pulley is shown here?
Wedge
What type of simple machine are the examples above?
inclined plane
What type of simple machine is Moby using to gain a mechanical advantage?
lever
What type of simple machine is a broom?
lever
What type of simple machine is a seesaw?
lever
What type of simple machine is a tennis racket? or all athletic equipment with a "handle"
lever
What type of simple machine is an arm?
lever
What type of simple machine is an ice cream scoop?
the distance gets longer
When a simple machine helps reduce the force, what happens to the distance needed to do the work?
mechanical advantage
When a simple machine increases the force. "It makes effort easier."
movable pulley
Which type of the two pulleys gives the user a mechanical advantage?
1. the load and fulcrum are best buddies:) 2. the effort is as far away from the fulcrum as possible
Why would Archimedes be able to "lift the world"? Two reasons.
screw
a spiral inclined plane that increase force to move deep inside something.
inclined plane
allows you to push or pull instead of lift, a ramp is an example.
effort force
amount of force needed to move something
pulley
can be fixed or moveable, can change the direction of force or decrease the effort force, the more you use the less force you need.
gears
can work with a wheel and axle, larger ones are easier to turn, can change the direction and amount of force
inertia
causes objects at rest to remain at rest and objects in motion to remain in motion
lever
consists of 2 parts a bar and fulcrum, there are 3 types, makes it easier to lift things.
wheel and axle
has 2 parts, one part is a bar that passes through the other part, the bar turns a small force into a larger force
spring scale
instrument used to measure FORCE
simple machines
lever, pulley, wheel and axle, inclined plane, wedge, and screw
load
object being lifted or moved
simple machines
one of six objects that help you do work includes levers, pulleys, wheels and axles, inclined planes, wedge, screw, and gears
wedge
pushes things apart by changing the direction of the force
effort
same as "force" (a push or a pull)
energy
the ability to do work
efficiency
the amount of useful work a machine puts out compared to the amount of work that is put in
speed
the distance traveled in a certain amount of time
friction
the force that acts against objects in motion when one surface touches another
Force x Distance = Work
the formula for measuring "work"
fulcrum
the point where a lever arm "pivots"
joules
the unit used for "work"
work
when force is used to move an object, only occurs when something moves
