In: Physics
8. How do people take advantage of thermal expansion for practical purposes? How can thermal expansion cause problems for people?
10. A sealed jar contains only air at room temperature and atmospheric pressure. To what temperature must the air be heated in order for its pressure to double? Give a number, and include units.
Example of thermal expansion on the part of a liquid can be found inside the car's radiator. If the radiator is "topped off" with coolant on a cold day, an increase in temperature could very well cause the coolant to expand until it overflows. In the past, this produced a problem for car owners, because car engines released the excess volume of coolant onto the ground, requiring periodic replacement of the fluid.
talking about problems, Long bridges sometimes expand up to a meter in hot weather, like the Golden Gate Bridge at the start of the chapter, or the Benjamin Sheares Bridge in Singapore. Without allowance for expansion, such structures are at risk of damage in very hot weather. Bridges and metal girders on building have expansion gaps or a free end resting on rollers to allow for expansion. In this way, when the weather is very hot, the will not be damaged.
2. For pressure to be doubled, at constant volume( jar) , the temperature shuold be doubled
PV = nRT