Mobile Learning Activity: Practical Application of Energy Changes

By the end of this mini course, you should be able to ...

What is a radiator?

Radiator

Car Radiator

A radiator is a device in a car that uses water and a coolant to keep the car's engine from overheating.  If a car's engine overheats, the metals that make up the engine can become soft and change shape.  This will not allow the engine to function properly.  The engine will become useless. 

Car radiator: Energy Changes involved

Energy Changes in a Car's Radiator

Heat exchange in the engine: coolant

The water and coolant in a car's radiator are pumped through tubes that surround the engine.  Here, heat energy is transferred from the engine to the water and coolant, increasing it's temperature.  The image at the right shows the energy bar chart for the coolant in the tubes that surround the engine.  

The energy bar diagram shows that the coolant remains a liquid (no change in phase energy, Eph) but that its thermal energy (Eth) increases as it passes through the engine.  

Heat exchange in the engine: engine

When the coolant runs past the engine, the engine transfers its heat energy to the coolant, becoming cooler. The image at the left show the energy bar chart for the engine as the coolant runs past it.  

The energy bar diagram shows that the engine remains a solid (no change in phase energy, Eph) but that its thermal energy (Eth) decreases as the coolant passes through the engine.  


Heat exchange at the radiator: coolant

When the coolant reaches the radiator, it releases heat energy to the air, becoming cooler.  The image at the right shows the energy bar chart for the coolant when it is in the radiator.  

The energy bar chart shows that the coolant remains a liquid (no change in phase energy Eph) but that its thermal energy (Eth) decreases as the coolant passes through the radiator. 

Heat exchange at the radiator: air

When the coolant reaches the radiator, it releases heat energy to the air, making the air's thermal energy increase.  The image at the left shows the energy bar chart for the air in contact with the radiator.

The energy bar chart shows that the air remains a gas (no change in phase energy Eph) but that its thermal energy (Eth) increases as the coolant passes through the radiator. 

Quiz

The function of a car radiator is

  • to provide heat to the passengers
  • to provide heat to the engine
  • to remove heat from the engine
  • to remove heat from the radiator

The following energy diagram show what occurs...

  • to the coolant at the engine
  • to the coolant at the radiator
  • to the engine as the coolant passes
  • to the air as the coolant passes through the radiator

The following energy diagram show what occurs...

  • to the coolant at the engine
  • to the coolant at the radiator
  • to the engine as the coolant passes
  • to the air as the coolant passes through the radiator