energy

1. Energy
• Energy – ability to do work
• Law of conservation of energy – energy
cannot be created or destroyed but can be
changed from one form to another
• Energy efficiency – the amount of useful
energy after a conversion – the more
efficient the more energy that can be used
• Ex: shape of car, shape of plane, houses,
windows

2. • Energy conversion – when a form of
energy is changed to another form of
energy
• 9 Types of Energy

3. 1. Kinetic energy(KE= vm2
/2)– energy in
motion Faster an object is moving the greater the kinetic energy, also the more
mass an object has the greater the kinetic energy

4. 2.Potential – energy due to the
objects position (object could
move)
Gravitational potential energy – energy
against the force of gravity—lifted objects
have GPE

5. Formula KE= mv2
/2

6. 3. Mechanical energy – Has
both kinetic + potential

7. • 4.Thermal energy – all the kinetic energy
due to motion of particles that make up
the object (faster the particles move the
greater the thermal energy)
• 5.Chemical energy – energy of a
compound that changes as its atoms are
rearranged, a form of potential energy

8. • 6.Electrical energy – energy of moving
electrons, a form of potential energy since
motion only happens when object is connected
to actual output
• 7.Sound energy – vibrating object transmit
energy through matter (S-L-G)
• 8.Light energy – vibration of electrically
charged particles, doesn’t need to be carried
through matter, can travel in a vacuum (area
with no matter-- SPACE)
• 9.Nuclear energy – energy from the change in
the nucleus of an atom

9. 2 kinds of nuclear energy
• Nuclear fusion – the joining of atoms (H)
• Ex: when hydrogen is fused together at
very high speeds to form helium (stars are
nuclear reactors on a massive scale), the
process releases tremendous amounts of
energy
• Nuclear fission – the splitting of an atom
• Ex: when uranium is split, the potential
energy in the nucleus is given off and
used in nuclear power plants to generate
electrical energy

12. • Electrical Energy– can be changed into
thermal, sound, light and kinetic energy
(most common energy used)
• Energy conversions allow us to maintain
our daily lives through machines
• Energy conversions always create a
certain amount of thermal energy for the
transition to take place

14. Types of conversions

15. Chemical Energy
• Photosynthesis – light energy to chemical
energy
• 6CO2 + 6H2O + light energy → C6H12O6 + 6O2
• Cellular respiration – humans using
chemical energy to kinetic energy
• C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP (energy)
• All chemical energy is potential energy.