Gas filled bulb and U-tube manometer

Relevant Resource questions :

Concepts demonstrated :

• radiation
• thermal expansion of air

Click on the picture to see a second picture

• Leslie's differential thermometer

Accessories (ie posters etc) :

Physics involved :

The black will absorb the light more thatn the clear bulb producing a greater change in the level of the mercury.

How to use the Demonstration :

• Monitor the temperature for the black bulb and for the clear bulb.
• Place hand on each bulb and watch the temperature change. NB one bulb should be black, the other clear.
• OR use a light.

Things to do or add :

• Clean and replace scale (laser print and laminate).
• Make the heat source remote.