Science Test Thermal Energy

Temperature

• A measure of the average kinetic energy (SPEED) of the particles in an object

• When particles SPEED UP the temperature INCREASES

• When the particles SLOW DOWN the temperature DECREASES

Thermal Energy

• Depends on an object or substances’:

  1. 1. TEMPERATURE (speed) (also known as average kinetic energy)

  2. 2. AMOUNT OF PARTICLES (mass)

  3. 3. Position (how particles are arranged) - don’t need to worry about this one

• The MORE particles an object or substance has at a given temperature the MORE thermal energy it has

• Two objects or substance can have the SAME thermal energy and have DIFFERENT temperatures IF the object with a LOWER TEMPERATURE has MORE PARTICLES to make up for the fact that the particles are moving slower

Heat

• Transfer of thermal energy from a warmer object to a cooler object

• Kinetic energy from the fast moving particles in the WARM object pass their kinetic energy to the particles of the COOL object

• When objects ABSORB heat the particles SPEED UP

• When an object LOSES or GIVES away heat the particles SLOW DOWN

Fahrenheit Scale

• 32 degrees = water melts/freezes (solid to liquid and liquid to solid)

• 212 degrees = water boils/condenses (liquid to gas and gas to liquid)

• 98.6 degrees = human body temperature

Celsius Scale

• 0 degrees = water melts/freezes (solid to liquid and liquid to solid)

• 100 degrees = water boils/condenses (liquid to gas and gas to liquid)

• Each degree of C is a larger change in particle movement than in degrees F (so a change in 1 degree C is a BIG deal compared to a change in 1 degree F which is a smaller change)

Kelvin Scale

• Used by scientists

• Developed because 0 (zero) on this scale actually means NO particle movement (which makes sense because temperature is a measure of particle movement)

Absolute zero

• The temperature at which all particle movement stop

• 0 kelvin

• Lowest possible theoretical temperature

• Nothing is this cold in temperature because it’s not possible (based on current theoretical astrophysics)

Convection

the transfer of heat by the movement of matter

Radiation

• the transfer of energy by electromagnetic waves.  

Conduction

the transfer of heat from one object to another by direct contact

Conductors

• A conductor is a material that conducts heat well.

• A conductor accepts thermal energy quickly and releases the thermal energy it has quickly

Insulators

• An insulator is a material that DOES NOT conduct heat well (the opposite of a conductor)

Specific Heat

Energy Change = mass x specific heat x change in temperature

Thermal Expansion and Contraction

• Thermal expansion is the expanding of matter (gas, liquid, or solid) when it is heated