Energy!

Woop Woop!

• Know that radiation is absorbed and emitted by all objects.

• Be able to compare the effectiveness of different surfaces as emitters, by considering the nature of the surface.

Think hard!

The hotter an object is the more infrared radiation it emits, but the type of surface also affects the rate at which radiation is emitted. You are going to investigate which surfaces are the best and worst at emitting radiation.

You will need:

2 x boiling tubes

2 x thermometers

2 x clamps and stands

1 x stopwatch

black card and tinfoil

Your teacher will show you how to set up the apparatus and give you a copy of the table below.  Stick the worksheet into your exercise book and record your results in the table.

Teacher note: higher tier groups might want to try this version instead (black, white and silver test tubes).

Think hard!

Work out the drop in temperature for each test tube.  Make a note of your findings by copying and completing the sentences below:

1) The temperature of the silver test tube decreased by ______ ˚C.

2) The temperature of the black test tube decreased by ______ ˚C.

3) The _________ test tube was emitting infrared radiation more rapidly.  The infrared radiation carried energy with it so the temperature _____________ more rapidly.  This means that __________ , __________ surfaces are more effective at emitting infrared radiation and _________, ________ surfaces are not as effective at emitting infrared radiation.