Terms in this set (45)
the ability to do work
Units for energy
J or nm
What are the forms of energy?
Electromagnetic, mechanical, chemical, sound, electrical, nuclear, and thermal
Law of Conservation of Energy
Energy cannot be created or destroyed, but it can be converted from one form to another
What are energy transfers or conversions
To change the type of form that it is in
Where does our energy come from and what form does it begin with
The sun the it is nuclear energy
What do all energy transfers end up as
What is potential energy
Stored or energy by position
What two factors affect potential energy in an object
Height and weight
What is kinetic energy?
energy of motion
What are the two factors of kinetic energy in an object
Mass and velocity
Why does velocity affect KE more than mass
Because it got squared
Why should you drive close to the speed limit
That way your speed does not get squared too much
What are the KE and PE formulas
KE= mass times velocity squared divided by 2 pe: weight times height
What is thermal energy
A form of energy from the movement of molecules
What is the Kinetic Molecular theory?
Hot- faster and further cold- slower and closer
What is temperature
Measurement of the movement of the molecules
C- 0° F- 32°
What is absolute zero?
Temperature at which all molecular movement stops completely
Three forms of heat transfer
conduction, convection, radiation
What is mass
the amount of matter in an object
What is weight
A measure of the force of gravity on an object
What is motion
A change in position compared to a reference point
What is speed
The distance travelled in a certain period of time
How is speed calculated?
What is acceleration
A change in velocity over a certain period of time
How is acceleration calculated?
Speed + direction
What is a force
A push or a pull
What is needed to get an object to stop or to move
What is Newton's first law?
An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
What is Newton's second law?
Acceleration is produced when a force acts on a mass.
Acceleration of a bowling ball
What is Newton's third law?
For every action there is an equal and opposite reaction
What is work
Force applied to an object and distance the object moves
What is the formula for work
How is the work formula the same as the pe formula
They are both force times the distance
What is conduction
transfer of heat by direct contact
What is Convection
Transfer of heat through currents. Hot air rises cold air sinks
What is radiation
Outward transfer of thermal energy by waves though space or air
What is insulation
Material that does not conduct heat well, ie. air
Trapped air in the fluff acts as an___________ & prevents _____________
Insulator & heat transfer
What does tip stand for?
T- Trapped air I- Insulates P- Prevents (or slows) heat transfer
Why do we use a blanket
It traps heat
Convention depends on