Energy and Heat Transfer

Which of the following is the correct definition of mechanical energy?

• energy an object has because of its motion or position

• energy resulting from the flow of charged particles, such as electrons or ions

• energy produced from the splitting of atoms

• energy stored in chemical bonds of molecules

When a warm object is placed near or in contact with a cooler object, which type of energy will be transferred?

• thermal energy

• mechanical energy

• chemical energy

• electrical energy

Which of the following is the correct definition of electrical energy?

• energy stored in chemical bonds of molecules

• energy of an object due to the random motion of its atoms and molecules

• energy resulting from the flow of charged particles, such as electrons or ions

• energy that is transmitted in the form of electromagnetic waves

Pat pours cold, liquid cream into a cup of hot coffee. Which of the following describes how the hot coffee and cold cream will interact?

• The cold cream will remain at the surface. When it warms, some of it will fall to the bottom of the cup.

• The cold cream will drop to the bottom of the cup. It will remain there, unless it is stirred.

• The cold cream will immediately reach the same temperature as the coffee and spread evenly though the cup.

• The cold cream will drop to the bottom of the cup. When it warms, some of it will rise back to the surface.

Heat energy is the transfer of _______ energy.

• chemical

• thermal

• nechanical

• electrical

Cindy makes herself a cup of hot chocolate on a very cold day. If Cindy's hands are very cold and the cup is very hot, heat energy transfers from the cup to her hands because

• of the size difference between them.

• one is a solid and the other is mostly a liquid.

• of the temperature difference between them.

• cold energy spreads from cool objects to warm objects

A slice of cheese is 3.0°C and is sitting on a dish that is 3.0°C. If the dish and cheese are in a refrigerator that is set to 3.0°C, which of the following statements is true?

• Heat will flow from the air in the refrigerator to the cheese and the dish.

• Heat will not flow because there is no temperature difference between the substances.

• The temperature of the air in the refrigerator will decrease and the temperature of the cheese will increase.

• The temperature of the cheese will increase and the temperature of the dish will decrease.

Which of the following is the correct definition of conduction?

• the transfer of heat by currents within a liquid or gas

• the electromagnetic radiation from the surface of an object which is due to the object's temperature

• the transmission of heat across empty space

• the transmission of heat across matter

Which of the following is an example of heat transfer by radiation?

• a fire warming a group of campers

• the Sun warming the Earth

• an electric space heater warming a room

• all of these

The heat from the Sun must pass through the vacuum of space before it reaches the Earth. Which process is illustrated in this example?

• radiation

• convection

• conduction

• induction