3b-scientific Radiation of Heat__Crookes Radiometer User Manual download pdf

Instruction Sheet

3B SCIENTIFIC® PHYSICS

U14300 Crookes radiometer

5/03 ALF

The Crookes radiometer is used for demonstrating the

conversion of radiation energy into kinetic energy.

1. Safety instructions

• Caution! Handle the glass vessel carefully to avoid

breakage and resulting injury.

2. Description, technical data

The apparatus consists of a rotary-vane wheel mounted

on a metal tip and equipped with four vertical plates

connected to a shaft that is free to rotate around a vertical

axis. Each vane is colored black on one side. It is housed

in a more or less evacuated glass bulb.

Height: 210 mm

Ball diameter: 80 mm

3. Operation and operating principle

• Allow light from the sun, from a light bulb or the heat

from an oven to incident on the radiometer.

• The vane wheel starts rotating with the bare surfaces

leading.

3B Scientific GmbH • Rudorffweg 8 • 21031 Hamburg • Germany • www.3bscientific.com • Technical amendments are possible

The rotation is caused by a temperature difference be-

tween the plain surface and the blackened surface of the

vaned wheel (turbine), which produces a slight differ-

ence in the gas pressure on the two surfaces.

Incoming photons are mostly absorbed by the black

vanes and mostly reflected by the bright vanes. The

air next to the black vanes is then hotter, and so the

air molecules there have greater average kinetic

energy, pushing the black vanes and causing the

device to spin.

• Heat the radiometer over a radiator to just above

room temperature.

• Screen it against direct radiation.

• The vane rotates for a short time in opposite direc-

tion.

Heat is transported in the opposite direction and the

blackened surfaces cool off more rapidly than the bright

vanes.

This second experiment proofs that the rotation is not

caused by the radiation pressure of the incident radiation

but by the greater recoil.

Summary of Contents

Page 1 - U14300 Crookes radiometer

2Instruction Sheet3B SCIENTIFIC® PHYSICSU14300 Crookes radiometer5/03 ALF®The Crookes radiometer is used for demonstrating theconversion of radiation

3b-scientific Radiation of Heat__Crookes Radiometer User Manual

Browse online or download User Manual for Health and hygiene 3b-scientific Radiation of HeatCrookes Radiometer. 3B Scientific Radiation of HeatCrookes Radiometer User Manual [de]

Summary of Contents

More documents for Health and hygiene 3b-scientific Radiation of Heat__Crookes Radiometer

Comments to this Manuals

3b-scientific Radiation of Heat__Crookes Radiometer User Manual

Browse online or download User Manual for Health and hygiene 3b-scientific Radiation of Heat__Crookes Radiometer. 3B Scientific Radiation of Heat__Crookes Radiometer User Manual [de]

Summary of Contents

More documents for Health and hygiene 3b-scientific Radiation of Heat__Crookes Radiometer

Comments to this Manuals

Related products and manuals for Health and hygiene 3b-scientific Radiation of Heat__Crookes Radiometer

Browse online or download User Manual for Health and hygiene 3b-scientific Radiation of HeatCrookes Radiometer. 3B Scientific Radiation of HeatCrookes Radiometer User Manual [de]