Heat Temperature

What happens to the length of a metal rod when it is heated?

• nothing, it will stay the same length

• it will get longer due to the thermal expansion

• it will get shorter due to the thermal contraction

You are frying pork chops in an iron skillet. If you grab the skillet, you can burn your hand. This type of heat transfer is called _____________________.

• radiation

• convection

• conduction

Hurricanes form due to the heating and cooling of air over warm ocean waters. Air warms up and rises, then cools off and falls. This sort of heat transfer is called ________________.

• Radiation

• Conduction

• Convection

Sometimes, the first law of thermodynamics is referred to in association with the law of conservation of energy. Which of the following best reflects the first law of thermodynamics?

• Heat cannot increase without a decrease in molecular vibration.

• Heat cannot be created unless energy is destroyed.

• Heat energy is never lost, only converted to a different form.

• Heat cannot be transformed, only destroyed.

A car engine uses 1000J of chemical energy while increasing the kinetic energy of the car by 300J. How much waste heat is produced by the engine?

• 700J

• 300000J

• 1300 J

• 3.33J

Which of the following is not an example of entropy?

• If you spray cologne at the front of the room, eventually people in the back can smell it.

• Ice will eventually melt in a drink.

• When touching a metal faucet, it feels cold.

• All of the oxygen moves to one side of the room, leaving a vacuum in the other side.

A piece of foam will feel warmer than a piece of metal at the same temperature. Why is this the case?

• Because foam is a conductor and metal is an insulator.

• Foam has more thermal energy the metal.

• Metal has less thermal energy than foam.

• Because foam is an insulator and metal is a conductor.

A glass sitting on a table is in thermal equilibrium with the table. A coffee cup sitting on the same table is in thermal equilibrium with the table. Which law of thermodynamics would say that the coffee cup and the glass are in thermal equilibrium with each other?

• 2nd

• zeroth

• 3rd

• 1st

Has a material approaches absolute zero, its entropy value approaches a constant value. This phenomenon is explained in the __________ law of thermodynamics.

• 3rd

• 1st

• zeroth

• 2nd

A convex lens is used to direct sunlight onto a piece of paper until the paper catches fire. What sort of heat transfer is being used to start the fire?

• Convection

• Conduction

• Radiation