Physical States and Temperature

Temperature

Physical Science

Temperature

In physics, temperature is defined as the average kinetic
energy of the particles of matter.

When particles of matter move more quickly, they have more
kinetic energy, so their temperature is higher.

Multiple Choice

Kinetic energy is the energy of ____________?

• Motion

• Position

• Gravity

• Heat

Multiple Choice

Temperature is a measure of ?

• Heat

• Cold

• The motion of molecules in a substance.

• Calories used.

Heat Transfer

Thermal Energy moves from hot to cold until it reaches equilibrium.

Once equilibrium is reached, heat transfer stops, but the molecules continue to
move.

Multiple Choice

Heat transfer always goes from

• hot to cold

• cold to hot

• equal to unequal

Multiple Choice

The movement of molecules stops when...

• equilibrium is reached

• Heat transfer stops

• cold transfer stops

• Never

Multiple Choice

"Dynamic" equilibrium means ?

• The motion continues, but temperature has leveled off

• The heat transfer has begun

• The molecules are no longer in motion.

Thermometers

Many thermometers measure
temperature with a liquid that expands
when it gets warmer and contracts
when it gets cooler.

The red liquid rises or falls in the glass
tube as the temperature changes.
Temperature is read off the scale at
the height of the liquid in the tube.

Multiple Choice

The liquid expands inside a thermometer because?

• The molecules of the substance move faster

• The molecules of the substance get bigger

• The molecules multiply in the heat

Temperature Scales

Although some scientists use the Celsius scale.

The SI scale for measuring temperature is the Kelvin scale. I

The U.S. uses the Fahrenheit scale.

Multiple Choice

Which temperature scale is based on the freezing and boiling point of water?

• Kelvin

• Celsius

• Fahrenheit

Temperature scale conversion

To convert a temperature from Celsius to Kelvin, just add 273
to the Celsius temperature.

For example, 10 °C equals 283 Kelvin.

C to F

Converting between Celsius and Fahrenheit is more
complicated.

Celsius → Fahrenheit: (°C × 1.8) + 32 = °F

Fahrenheit → Celsius: (°F - 32) ÷ 1.8 = °C

Multiple Choice

80 C = F

• 176

• 44.4

• 12.4

• 144

Multiple Choice

76 F = C

• 44

• 24.4

• 12

• 349

Absolute Zero

The lowest temperature that is theoretically possible, at which
the motion of particles that constitutes heat would be
minimal.

It is zero on the Kelvin scale, equivalent to –273.15°C or
–459.67°F.

Multiple Choice

Absolute Zero

• All molecular motion has stopped

• An object is frozen

Heat

Heat

The transfer of thermal energy between substances.

Thermal energy is the kinetic energy of moving particles of
matter, measured by their temperature.

Thermal energy always moves from warmer to cooler
substances.

Multiple Choice

Thermal Energy

• the kinetic energy of moving particles of matter

• The transfer of cold between substances

• the potential energy of particles in matter.

Multiple Choice

Heat is

• The transfer of thermal energy between substances

• The measure of molecular motion in a substance

• The absence of cold

• really hot

Thermal energy

Transferred from
hot to cold, until
both substances
have the same
thermal energy and
temperature.

Multiple Choice

The transfer of energy from one substance to another will stop when?

• molecules stop moving

• Temperature is the same

• Both items are frozen

Specific Heat

A measure of how much energy it takes to raise the
temperature of a substance.

It is the amount of energy (in joules) needed to raise the
temperature of 1 gram of the substance by 1 °C.

Specific heat is a property that is specific to a given type of
matter.

Multiple Choice

Specific Heat

• A measure of how much energy it takes to raise the temperature of a substance.

• the kinetic energy of moving particles of matter

• The lowest temperature that is theoretically possible

Multiple Choice

All materials respond to heat at the same rate.

• true

• false

Metals such as iron have low specific heat.

It doesn’t take much energy to raise their temperature.

Sand also has a relatively low specific heat.

Water has a very high specific heat. It takes a lot more energy
to increase the temperature of water than sand.

Conduction

One of three ways that thermal energy can be transferred (the
other ways are convection and thermal radiation).

Is the transfer of thermal energy between particles of matter
that are touching.

When particles of warmer matter collide with particles of
cooler matter, they transfer some of their thermal energy to
the cooler particles.

Convection

● Convection is the transfer of thermal energy by particles

moving through a fluid.

● Moving particles transfer thermal energy through a fluid by

forming convection currents.

● Convection currents move thermal energy through many

fluids, including molten rock inside Earth, water in the
oceans, and air in the atmosphere.

Multiple Choice

What is responsible for "plate tectonics?

• Conduction

• Convection

• Radiation

• None of the above

Thermal Radiation

Thermal radiation is the transfer of
thermal energy by waves that can
travel through air or even through
empty space.

Everything radiates thermal
energy.

Multiple Choice

What radiates thermal energy?

• stars

• ice

• uranium

• everything

Conductors and Insulators

Good conductors of thermal energy are called thermal
conductors. Metals are very good thermal conductors.

Poor conductors of thermal energy are called thermal
insulators. Gases such as air and materials such as plastic
and wood are thermal insulators.

Open Ended

Explain how heat transfer is responsible for weather on planet earth.

Open Ended

How do the oceans help to stabilize earths climate? (Think heat NOT climate change!)