Heat Transfer Methods

Conduction

• Transfer of energy from one particle of matter to another within an object or between two objects that are in direct contact.

  
  

• Transfer of energy by electromagnetic waves

 Radiation

• Transfer of energy from one particle of matter to another within an object or between two objects that are in direct contact.

• Transfer of energy by electromagnetic waves

 Convection Current

• Heat transfer that occurs through the movement of fluids, which can be a solid, liquid, or gas

• The movement of a fluid, caused by differences in temperature, that transfers heat from one part of the fluid to another

Convention

• Heat transfer that occurs through the movement of fluids, which can be a solid, liquid, or gas

• The movement of a fluid, caused by differences in temperature, that transfers heat from one part of the fluid to another

Water is unique in that it exists in all three states on Earth. Which statement best describes what happens to the energy of the particles when water vapor begins to cool?

• The average potential energy decreases.

• The average kinetic energy decreases.

• The average potential energy remains the same.

On a hot summer day, a piece of ice is removed from a cooler and placed in a cup that is sitting on a picnic table. Which of the following statements are true about what happens to the ice and the cup over time? Choose the two that apply.

• The particles in the ice start to move faster.

• Both the ice and the cup change state.

• The cup changes temperature.

We are constantly surrounded by many types of energy transfers and transformations, showing that energy in a system is conserved. Which of these statements are true about how energy is conserved through transfers and transformations? Choose the two that apply

•  Energy is conserved when a lamp is turned on because some of the electrical energy is transferred into thermal energy.

• Energy is conserved when thermal energy is transferred from your body to a coat

• Energy is conserved when some of the chemical energy from burning a candle is transformed into thermal energy, while the rest chemical energy is transformed into light energy.

  
  

Which choice shows the energy transformations that occur when a light bulb heats up after it has been turned on?

• electrical, light, thermal

• chemical, electrical, thermal

• chemical, electrical, light

When you make a campfire, what you see is the result of energy transformations. Pick the types of energy below in the correct order. Order the starting type of energy “1” and the final type of energy “3.”

• Chemical, Thermal, Light

• Thermal, Light, Chemical

• Chemical, Light, Thermal

In mid-summer, a family assembled a patio set for their deck. Most of the assembling was done by placing metal screws into plastic holes. The furniture was stable throughout the summer. However, when the weather turned cold in the late fall, the family noticed that the chairs and table became wobbly. Which statement best explains what happened?

• Plastic has greater thermal expansion than metal does.

• Both plastic and metal contract when warm and expand when cold.

• The metal screws contracted more than the plastic did when they

  became cold.