Heat Transfer: Scenarios

Which choice is an example of conduction?

• The sun gives off light. The light transfers through open space, and Earth receives some of this light.

• Hot air exists near Earth’s surface. This hot air rises, and then colder air moves downward toward Earth’s surface.

• A person places a cold apple on a warm plate. Heat transfers from the warm plate to the cold apple.

• A person fills a balloon with helium. The person releases the balloon, and it rises because it is less dense than the surrounding air.

An ice cube in the palm of a person’s hand is shown. Which best describes the transfer of energy in the picture?

• Heat is being transferred from the person’s hand to the ice by convection.

• Coolness is being transferred from the ice to the person's hand by convection.

• Coolness is being transferred from the ice to the person's hand by conduction.

• Heat is being transferred from the person’s hand to the ice by conduction.

Which statement best describes the type of heat energy responsible for making the “marks” on the piece of meat?

• Convective heat from the air marks the meat

• Radiant heat from the charcoal marks the meat.

• Conductive heat from the metal grates marks the meat.

• Thermal heat from both sides of the metal grill marks the meat.

A cup of hot chocolate is mixed with a metal spoon. Which statement best explains how heat is transferred between the hot chocolate and the part of the spoon that is in the hot chocolate?

• Convection transfers energy from the hot chocolate to the spoon.

• Conduction transfers energy from the hot chocolate to the spoon.

• Convection transfers energy from the spoon to the hot chocolate.

• Conduction transfers energy from the spoon to the hot chocolate.

How does energy transfer when an ice cube is placed in a cup of room-temperature liquid water?

• Heat flows from the liquid water to the ice cube.

• Heat flows from the ice cube to the liquid water.

• Cold flows from the liquid water to the ice cube.

• Cold flows from the ice cube to the liquid water.

A scoop of ice cream is placed on top of a hot brownie. How will the temperatures of the ice cream and the brownie change?

• The ice cream will become warmer than the brownie.

• The brownie will become warmer than the ice cream.

• The ice cream will become warmer, and the brownie will become colder.

• The brownie will become warmer, and the ice cream will become colder.

Bill and Avery want to do an experiment to show convection. Which is the best cooking example of convection they can model?

• frying eggs

• icing a cake

• boiling water

• melting chocolate

A crayon, placed on a dark driveway in bright sunlight, melted into a colorful puddle. What caused the crayon to melt?

• Solar convection heated the driveway, and then the heat was transferred to the crayon by conduction.

• Solar radiation heated the driveway, and then the heat was transferred to the crayon by conduction.

• Solar convection heated the driveway, and then the heat was transferred to the crayon by radiation.

• Solar radiation heated the driveway, and then the heat was transferred to the crayon by radiation.

After taking a hot shower, Tim steps out onto the tile floor. The tile feels cold to his feet. Which best describes Tim’s experience?

• Cold from the tile is transferred to Tim’s feet.

• Cold from Tim’s feet is transferred to the tile.

• Heat from the tile is transferred to Tim’s feet.

• Heat is transferred from Tim’s feet to the tile.

Which statement best describes what happens to water that is heated to a boil in a pot?

• Cold water rises, and hot water sinks.

• Cold water sinks, and hot water rises.

• Cold water remains in place, and hot water rises.

• Hot water remains in place, and cold water sinks.