This is one of the earliest versions of a BBC logo. It is found at the centre of the original mosaic floor in the reception of Broadcasting House, London. Completed in 1932, Broadcasting House is a jewel of Art Deco design, which integrated a wide range of artists and designers in the conception and embellishment of the UK's first ever purpose-built radio centre. Bell, Mary; Green, S. E. (1933). "On Radiometer Action and the Pressure of Radiation". Proceedings of the Physical Society. 45 (2): 320–357. Bibcode: 1933PPS....45..320B. doi: 10.1088/0959-5309/45/2/315. . 1933 Bell and Green experiment describing the effect of different gas pressures on the vanes. The currently accepted theory was formulated by Osborne Reynolds, who theorized that thermal transpiration was the cause of the motion. [11] Reynolds found that if a porous plate is kept hotter on one side than the other, the interactions between gas molecules and the plates are such that gas will flow through from the cooler to the hotter side. The vanes of a typical Crookes radiometer are not porous, but the space past their edges behaves like the pores in Reynolds's plate. As gas moves from the cooler to the hotter side, the pressure on the hotter side increases. When the plate is fixed, the pressure on the hotter side increases until the ratio of pressures between the sides equals the square root of the ratio of absolute temperatures. Because the plates in a radiometer are not fixed, the pressure difference from cooler to hotter side causes the vane to move. The cooler (white) side moves forward, pushed by the higher pressure behind it. From a molecular point of view, the vane moves due to the tangential force of the rarefied gas colliding differently with the edges of the vane between the hot and cold sides. [3]

BBC Revolving World BBC - A History of the World - Object : BBC Revolving World

The BBC has all eight Royal Charters. It started life as a Company, but changed to a Corporation following a report by the Crawford Committee. The Government accepted the Committee's findings and established by Royal Charter the British Broadcasting Corporation. The Charter set out the way in which the BBC would be governed. The prefix " radio-" in the title originates from the combining form of Latin radius, a ray: here it refers to electromagnetic radiation. A Crookes radiometer, consistent with the suffix " -meter" in its title, can provide a quantitative measurement of electromagnetic radiation intensity. This can be done, for example, by visual means (e.g., a spinning slotted disk, which functions as a simple stroboscope) without interfering with the measurement itself. Metal World Map, Metal Wall Decor, Metal Wall Art, World Map Wall Art, Metal Art, Housewarming Gift, Wall Hanging (97x56 cm/ 118x68 cm) Metal World Map Wall Art, World Map Compass Continent, Metal Wall Decor, Interior Decoration, Wall Hanging Home Office Decor 5 Color OptionsThe BBC 2 'Flycatcher' ident. This ident was computer generated, but several original 2 models survive and are on display at various BBC buildings. BBC mosaic logo Raindrop Modern Globe Chandelier Staircase Lighting Tall Long Chandelier Adjustable Length Multi Lighting for Dining Room Long Chandelier

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Ohio, The University of Akron. "the radiometer using inquiry to teach energy conversions". The University of Akron, Ohio . Retrieved 10 October 2021.John Lewis plc, registered office: 171 Victoria Street, London SW1E 5NN. Authorised and regulated by the Financial Conduct Authority (Register no. 724309) for the purpose of introducing the credit provided by Creation Consumer Finance Ltd, registered office: Wellington Buildings, 2-4 Wellington Street, Belfast BT1 6HT. Keep collections to yourself or inspire other shoppers! Keep in mind that anyone can view public collections - they may also appear in recommendations and other places. The Crookes radiometer (also known as a light mill) consists of an airtight glass bulb containing a partial vacuum, with a set of vanes which are mounted on a spindle inside. The vanes rotate when exposed to light, with faster rotation for more intense light, providing a quantitative measurement of electromagnetic radiation intensity.