ch22.ppt

Open Ended

Why is it important to understand the different ways heat can be transferred, such as conduction, convection, and radiation, in our daily lives?

Multiple Choice

When several objects at different temperatures are placed near each other, what will eventually happen to their temperatures?

• They will all reach the same temperature.

• The warm objects will get warmer and the cool objects will get cooler.

• Their temperatures will remain unchanged.

• Only the largest object will change temperature.

Fill in the Blanks

Materials that conduct heat well are known as heat

.

Multiple Choice

Which of the following best describes the process of conduction as explained in the slides?

• Transfer of thermal energy through collisions between particles without overall transfer of matter

• Transfer of matter along with energy

• Transfer of energy through radiation only

• Transfer of energy by convection currents

Open Ended

Explain how the energy of vibrating atoms changes along the length of a metal rod when one end is heated by a flame.

Multiple Choice

Which of the following is NOT a reason why metals are good conductors of heat?

• They have loosely bound outer electrons.

• Their atoms vibrate more rapidly when heated.

• They have tightly bound electrons that do not move.

• Free electrons can transfer energy by colliding with atoms and other electrons.

Multiple Select

Which of the following statements about conductors is/are correct?

• Materials with loose outer electrons are good conductors of heat.

• Metals are the best conductors of heat and electricity.

• All materials conduct heat equally well.

• Good conductors of heat are always good conductors of electricity.

Open Ended

Why does metal feel colder than wood even if both are at the same temperature?

Multiple Choice

Why does a tile floor feel colder to bare feet than a carpet at the same temperature?

• Because tile is a better conductor of heat than carpet

• Because tile is colder than carpet

• Because carpet is a better conductor of heat than tile

• Because tile absorbs more heat from the feet

Multiple Select

Which of the following materials are considered good insulators due to the air spaces they contain?

• Wool

• Polystyrene

• Feathers

• Metal

Fill in the Blanks

A 'warm' blanket does not provide you with heat; it simply slows the transfer of your body heat to the

.

Multiple Choice

What is the main purpose of insulation in a home according to the slides?

• To keep the cold out

• To keep the heat in

• To prevent air flow

• To make the house look better

Open Ended

Why does snow last longer on the roof of a well-insulated house compared to a poorly insulated one?

Open Ended

If you hold one end of a metal bar against a piece of ice, the end in your hand will soon become cold. Does cold flow from the ice to your hand?

Multiple Choice

Which of the following statements best explains why metal feels colder than wood at the same temperature?

• Metal is a better conductor of heat than wood.

• Wood absorbs more heat than metal.

• Metal is always colder than wood.

• Wood is a better conductor of heat than metal.

Open Ended

You can place your hand into a hot pizza oven for several seconds without harm, whereas you’d never touch the metal inside surfaces for even a second. Why?

Open Ended

How does conduction transfer heat?

Multiple Select

Which of the following are methods of heat transfer?

• Conduction

• Convection

• Radiation

• All of the above

Fill in the Blanks

Fill in the blank: In convection, heat is transferred by movement of the

substance from one place to another.

Multiple Choice

Which of the following best describes convection as a method of heat transfer?

• Movement of heated substance itself, such as by currents in a fluid

• Transfer of heat through direct contact between molecules

• Transfer of heat by electromagnetic waves

• Transfer of heat only in solids

Fill in the Blanks

When a fluid is heated, it expands, becomes less

, and rises.

Open Ended

Explain how convection currents are formed in fluids when they are heated.

Multiple Select

Which of the following statements about convection currents is/are correct?

• Convection currents transfer heat in air.

• Convection currents transfer heat in liquids.

• Convection currents occur only in solids.

• Convection currents require the movement of the heated substance.

Multiple Choice

Why does the ice at the bottom of the test tube remain unmelted even when the water at the top is boiling?

• Because water is a poor conductor and convection is prevented

• Because ice is a good conductor of heat

• Because heat is transferred quickly to the bottom

• Because the flame is not hot enough

Open Ended

Describe what happens in the experiment where a piece of ice is trapped at the bottom of a test tube filled with water and the top is heated with a Bunsen burner.

Fill in the Blanks

Heat always transfers from ___ objects to ___ objects until all reach a common temperature.

Open Ended

Explain how the concept of heat transfer applies to everyday objects you encounter. Can you give an example from your own experience?