Download Geothermal energy

BIG IDEA: ENERGY CAN
TRANSFORM FROM ONE KIND
TO ANOTHER, AND IT CAN
TRANSFER FROM ONE OBJECT
TO ANOTHER, BUT IT CAN
NEVER BE CREATED OR
DESTROYED
CHAPTER 6: ENERGY
6.1-6.3 SUMMARY
Should be able to answer:
Equation for work???
Work= force x distance
Work is done when the object moves in what
direction of the net force
direction?
Equation for power???
power=
Unit of power:
Watt
𝑤𝑜𝑟𝑘 𝑑𝑜𝑛𝑒
𝑡𝑖𝑚𝑒 𝑖𝑛𝑡𝑒𝑟𝑣𝑎𝑙
Unit of work:
Joules
Two types of mechanical energy???
Potential and kinetic
6.4 POTENTIAL ENERGY IS STORED
ENERGY
The potential energy due to elevated position
is gravitational potential energy.
The amount of gravitational potential energy
possessed by an elevated object is equal to
the work done against gravity in liftingit
Gravitational potential energy= weight x
height
PE=mgh
6.5 KINETIC ENERGY IS ENERGY OF
MOTION
Kinetic energy= ½ mass x speed2 or KE= ½ ms2
Kinetic energy depends on speed and mass
Is something has a certain amount of KE, when it
moves twice as fast it has 22 or four times as
much KE!
Three times the speed= ________ times energy
Four times speed= ____________times energy
6.6 WORK-ENERGY THEOREM
Work= ∆KE
∆=“Change in”
The work-energy theorem states that whenever
work is done, energy changes
-When there is no change in energy we can
say that no work was done
The more KE something has, the more energy is
required to stop it
6.7 CONSERVATION OF ENERGY
Energy cannot be created or
destroyed; it may be transformed
from one form into another or
transferred from one object to
another, but the total amount of
energy never changes.
The PE of an elevated ram is
converted to KE when it is released
Suns energy plants animals
humans earth (decomposers)
6.8 MACHINES- DEVICES TO MULTIPLY
FORCES
Machine- device for multiplying forces, or changing the
direction of forces.
A machine transfers energy from one place to another or
transforms it from one form to another.
(Force x distance)input= (force x distance)output
Fulcrum
Examples of simple machines:
Lever
Pulley
Can multiply force, but not
work or energy
Any machine that multiplies
force does so at the expense of
distance
-A pulley only changes the
direction on input force
6.9 EFFICIENCY-A MEASURE OF WORK
DONE FOR ENERGY SPENT
A machine that can do more work is said to be more
efficient
Efficiency=
𝑤𝑜𝑟𝑘 𝑑𝑜𝑛𝑒
𝑒𝑛𝑒𝑟𝑔𝑦 𝑢𝑠𝑒𝑑
-The lower the efficiency of a machine, the greater
amount of energy is wasted as heat
ALTERNATIVE SOURCES OF ENERGY
Most energy that we use comes from the burning of
fossil fuels
Renewable resource- a resource that is present in
great abundance and is continually produced.
Solar power- collect energy from the Sun
Wind power- Turbines powered by wind use
generators to convert wind to energy we can use
Geothermal energy- Taking the heat from inside the
Earth to use as electricity
Hydroelectricity- converts falling water to
electricity
Biomass- organic matter in plants.
-Unlike the energy sources previously discussed,
biomass is NOT specific to a particular climate or
location
Biodiesel is a fuel made from pure oils of plants
such as soybeans, corn, and peanuts
Biodiesel may be a leading biomass energy
source for the future