Energy Exit Ticket

Which direction does thermal energy transfer?

• Cold to hot

• Hot to cold

• Either direction

• Neither, they just mix

How does thermal energy transfer?

• Faster particles move past other particles.

• Slower particles bump into faster particles, slowing them down

• Particles vibrating at a higher speed bump into those next to them.

• The colder particles move.

A metal spoon has denser particles than a wooden spoon. If both were placed in a hot pot of water, which would be a better conductor?

• The metal spoon.

• The wooden spoon

• Both spoons would be equal conductors

• It depends on the heat of the water.

The Willy Warm Gloves were an example of a good:

• Insulator

• Conductor

Why is air a good insulator in between window panes?

• Air on its own is warmer than all solids

• Air is a gas, so the particles are farther apart and cannot conduct thermal energy as easily.

• Air is a gas, so its higher density of molecules allows it to conduct thermal energy easily

• Air on its own is cooler than all solids.

Thermal energy transfers in one direction. Supporting evidence will vary depending on materials used, but students may use the example of the heat from their hands moving through material, such as foil, and increasing the temperature shown on their thermometer.

Fill in the blanks to describe one piece of evidence from your investigations to back up your claim. Thermal energy transfers from _____ to ______. *include to in your answer*

Do you think aluminum foil is a good insulator or conductor? Why? Only one is right.

• Foil is a good conductor, because the heat from my hands caused a faster increase in temperature than with the other materials, such as bubble wrap. Meaning The particles are close together, so the heat energy in the form of vibrations is transferred easily between the particles, causing a more rapid increase in temperature.

• Foil is a good insulator, because the heat from my hands caused trapped the temperature than with the other materials, such as bubble wrap. Meaning The particles are far away together, so the heat energy in the form of vibrations is transferred easily between the particles, causing a slower increase in temperature.

Observe the picture. Which of these samples has more kinetic energy in the particles? Explain why.

• Picture A. The particles have kinetic energy, which occurs as a result of temperature.

• Picture B. The particles have more kinetic energy, which occurs as a result of increase in temperature.

Connect back to The Solve. Explain why bubble wrap gloves would or would not be good insulators.

• Bubble wrap are NOT a good insulator because it contains spaces that are able to trap air. The particles in the air aren't spread far enough apart; therefore, the heat energy is too easily transferred.

• Bubble wrap is a good insulator because it contains spaces that are able to trap air. The particles in air are spread far apart; therefore, the heat energy is not easily transferred.

When you put your hand in a cup of ice water, your hand feels cold. This is because ___________.

• Your hand gains the coldness from the ice water.

• Your hand loses thermal energy to the ice water

• The ice water loses thermal energy to your hand.

• The ice water loses thermal energy to your hand.