Heat

The transfer of heat in the atmosphere by winds that circulate between the equator and the poles is an example of

• radiation
• insulation
• convection
• conduction

Which of the following statements about thermal energy is true?

• As you hold a cup of hot water your hands cool the water.
• As you hold a glass of cold milk, the cold travels to your hand.
• As you hold a cup of cold milk, your hand cools the milk.
• As you hold a cup of hot water, the heat moves to your hand.

A student is mixing a cup of hot chocolate with a spoon. How is the heat transferred between the hot chocolate and the part of the spoon that is in the hot chocolate?

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

Which statement describes the transfer of energy when an ice cube is placed in a cup of hot tea?

• Heat flows from the tea to the ice.
• Cold flows from the ice to the tea.
• Cold flows from the ice, and heat flows from the tea.
• Heat flows simultaneously between the ice and the tea.

Miranda wraps her hands around a mug of hot tea. The heat from the hot tea is being transferred to Miranda’s hands primarily by

• conduction
• convection
• absorption
• radiation

Jennifer is in a room that has an air temperature of 25ºC (77ºF). Before pouring cold water into a glass, she notices that the ice in the pitcher is melting. What would be the BEST way for Jennifer to describe how thermal energy is being transferred?

• Heat moves from the ice to the water.
• Cold moves from the ice into the water.
• Heat moves from the air into the water.
• Cold moves from the water into the room.

Energy from the Sun reaches Earth by

• radiation
• conduction
• convection
• thermal expansion

A pan containing hot water is left on the counter and becomes cool mainly due to

• water molecules moving apart.
• cold air penetrating the hot water.
• heat from the water moving into the cooler air.
• hot water reacting with the metal pan.

One end of a metal rod is placed over a flame during an investigation. A thermometer is touching the opposite end of the metal rod. Which BEST describes what is happening during this investigation?

• Convection carries heat to the thermometer.
• Radiant energy warms the thermometer.
• Mechanical energy from the flame carries heat to the thermometer.
• Heat from the flame is conducted through the metal rod to the thermometer.

Hot objects begin to cool as

• cooler air is transferred to the object.
• energy in the object is transferred to the surrounding air.
• atoms in the object react with the oxygen in the air.
• energy in the object cancel out energy in the air.