1. A road free obstacle of concrete be made of piece pieces of length 14 m (20 0). How width distance expansion (At 20 0 C) must be made between piece piece said forprevent arch if the temperature range is -30 0 C to +50 0 c?
2. Super invar, an alloy of iron and nickel, is a strong material with thermal expansion coefficient is very low (0.2 x 10 -6 / 0 C). The top 2 m long table made of an alloy is used for the measurement of laser-sensitive which required a very high tolerance. How big is this mixture will expand along its length jka 5 0 C temperature rise?
3. To be more robust, larger than the nail holes and nails are often used then cooled (usually in dry ice) before it is placed in the hole. A 1.871-diameter steel nails will be placed in a hole with a diameter of 1.869 cm. To a temperature of how many nails must be cooled in order to get into the hole (initial temperature 20 0 C)
4. Estimate the percentage change in the density of the iron when it is still solid, but deep in the earth where the temperature of 2000 0 C and a pressure of 5000 atm. Assume Bulk modulus and volume expansion coefficient does not vary with temperature and the same at normal room temperature. The bulk modulus for steel is about 90 x 10 9 N / m 2.
5. An ordinary glass is filled to the brim with 350 mL of water at 100 0 C. If the fall of temperature up to 20 0 C, how much water can be added to the glass?
6. It appears that 65.5 ml of water at 20 C to meet a vessel to the brim. When the vessel and the water is heated to 60C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion vessel? (b) What is the material most likely to the vessel? The density of water at 60C is 0.98324 g / mL.
7. A 14.5 cm diameter quartz sphere. how changes in volume when heated from 30 0 C to 200 0 C?
8. A brass plug was placed in a ring made of iron. At room temperature, the plug is 8.753 cm diameter and the diameter of the ring is 8.743 cm. Temperature to how they should be taken to fit?
9. If the fluid is inserted into the vessel narrow and long so only expand in one direction, show that the effective linear expansion coefficient α approximately equal to the volume expansion coefficient β?
10. (a) Show that the change in the density ρ of a substance, when the temperature changes by ΔT given by Δρ =-βρΔT. (b) how much of the changes the density of lead balls the temperature decreases from 25 C to 40 C?
11. Show that for isotropic solids, β = 3α if the magnitude of the expansion is quite small. β and α is the volume expansion coefficient and length. [Hint: imagine a solid cube and ignore a very small scale. ]
12. The pendulum of a clock is made of brass and shows the time perfectly at 17 0 C. How penambhan or reduction of time in one year if the hours worked at 25 0C? (Assuming the frequency dependence on length for a simple pendulum)
13. A wheel cylinder of solid aluminum with a radius of 0.52 m rotates around its axis on bearings that do not rub with angular velocity ω = 32.8 rad / s. If the temperature is now raised from 20 C to 75 C, what fraction ω changes?
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