In a pressure dependent system, two zones. on the same system are effected by the control of one. another. Example â. Room A and Room B are two conference rooms. Both. are supplied by different VAV terminal units from the. same central air supply.
The color of a star depends on its surface temperature. Our Sunâs surface temperature is about 6,000 Kelvin. Although it looks yellow from here on Earth, the light of the Sun would actually look very white from space. This white light coming off of the Sun is because its temperature is 6,000 Kelvin.
Stars are often classified according to spectral type. Although they emit all colors of light, spectral classification considers only the peak of this emission as an indicator of the star's surface temperature. Using this system, blue stars are the hottest, and are called O-type. The coolest stars are red and are called M-type. In order of increasing temperature, the spectral classes are M (red), K (orange), G (yellow), F (yellow-white), A (white), B (blue-white), O (blue). This bland categorization is often abandoned for a more descriptive alternative. As the coolest stars (red) are invariably the smallest, they are called red dwarfs. Conversely, the hottest stars are often called blue giants. There are a number of physical characteristics that vary for each of the different types of star.