How does the sun make it spin!? This question has had scientists scratching their heads since 1873 when the radiometer was first invented by chemist William Crook...
How does the sun make it spin!? This question has had scientists scratching their heads since 1873 when the radiometer was first invented by chemist William Crook. The prevailing theory is one based on thermodynamics. What we do know is that the radiometers vanes rotate faster when exposed to more intense light. The instrument provides a quantitative measure of energy from light sources such as the sun, artificial globes, or infrared radiation - even the heat of a hand nearby can be enough to get the vanes moving. A great learning tool for any science classroom.
Ages: 10 +, under adult supervision
What you get
Crookes Radiometer. This is not a toy, the glass is fragile.
How does it work?
The airtight glass bulb has had much of the air removed creating a partial vaccum. Inside are a set of vanes which are mounted on a spindle and rotate when exposed to light (no batteries or electrical energy needed here to generate movement). It is thought that the radiometer, also known as a light mill, works like a heat engine when exposed to a radiant energy source like sunlight. Meaning it converts a temperature difference to mechanical output. In this case, the temperature difference is created by the black side of the vane becoming hotter than the other white side. Cooling the radiometer causes rotation in the opposite direction.
- Heat Engine (the radiometer effectively becomes a heat engine when a light energy is directed at it).
- Sustainable and solar energy.
- Black-body absorption the black vanes inside the radiometer heat up quickly because they absorb all radiation falling on them. This contrasts to the other white side of the vanes.
- Light energy and electromagnetic radiation.
WARNING: CHOKING HAZARD - Small Parts. Not for children under 3 years.
|Age Group||7-8 Years, 9-10 Years, 11-12 Years|
What are the shipping costs?
FREE Shipping is available on all orders over $120 to anywhere in Australia!
Orders under the value of $120 incur a low flat rate shipping cost of only $9.95 to anywhere in Australia.
Express, Registered and International delivery options are also available. The cost for these premium shipping services will be automatically calculated during the checkout process. Please conact us if you have any queries with these services.
In some cases we may need to apply a shipping surcharge to large or fragile items, especially to remote or non-urban locations. You will be contacted by us for confirmation if this additional charge is applicable.
How long will it take for my order to arrive?.
You should receive your order within 2 to 4 working days, although to some regional and out back areas it can take up to 2 working days longer. Orders going to WA also take a little longer, up to 6 working days.
All standard orders are shipped using Australia Post's eParcel service, so you'll be kept fully informed of the progress of your order during its journey to you. Aside from receiving regular email updates, you can enter your tracking number into Australia Post's website at any time for information about the delivery status of your order.
International delivery will take from between 1 to 4 weeks depending on the destination and potential customs clearance delays.
When will my order be shipped?
We ship every Victorian business day. Orders received and paid for by 12pm AEST time will generally be shipped the same day.
If you require your order urgently, we have a next day delivery express service available.
What locations do you ship to?
We ship to both Australian and International customers.
What shipping options are available?
The majority of orders are shipped using Australia Post's trackable eParcel service, with larger orders being sent by national courier.
We also have options for express or registered post. A number of international delivery options are also available. These can be selected during checkout.