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1. An ice cube of mass m and specific heat ci is initially at temperature T1, where T1 < 273 K. If L is the latent heat of fusion of water, and the specific heat of water is cw how much energy is required to convert the ice cube to water at temperature T2, where 273 K < T2 < 373 K?
m[ci(273 ­ T1) + L + cw (T2 ­ 273)]
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April 16, 2013
2. Two blocks of steel, the first of mass 1 kg and the second of mass 2 kg are in thermal equilibrium with a third block of aluminum of mass 2 kg that has a temperature of 400 K, What are the respective temperatures of the first and second steel blocks?
400 K and 400 K
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April 16, 2013
A piece of metal with a mass of 1.50 kilograms, specific heat of 200 J/kg / C°, and
initial temperature of 100° C is dropped into an insulated jar that contains liquid with a mass of 3.00 kilograms, specific heat of 1,000 J/kg · C°, and initial temperature of
0° C. The piece of metal is removed after 5 seconds, at which time its temperature is 20° C. Neglect any effects of heat transfer to the air or to the insulated jar.
8 oC
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April 16, 2013
A spring scale calibrated in kilograms is used to determine the density of a rock specimen. The reading on the spring scale is 0.45 kg when the specimen is suspended in air and 0.36 kg when the specimen is fully submerged in water. If the density of water is 1000 kg/m3, the density of the rock specimen is
5.0 x 103 kg/m3
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April 16, 2013
A gas with a fixed number of molecules does 32 J of work on its surroundings and 16 J of heat are transferred from the gas to the surroundings. What happens to the internal energy of the gas?
It decreases by 48 J.
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April 16, 2013
A 2­kilogram block of metal with a specific heat of 100 joules per kilogram • Kelvin falls from rest through a distance of 100 meters to the Earth's surface. If half of the potential energy lost by the fallen block is converted to internal energy of the block, the temperature change of the block is most nearly
5 K
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April 16, 2013
The maximum efficiency of a heat engine that operates between temperatures of 1500 K in the firing chamber and 600 K in the exhaust chamber is most nearly
60 %
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8. To get an idea of how much thermal energy is contained in the world’s oceans, estimate the heat liberated when a cube of ocean water, 1 km on each side, is cooled by 1K. (approximate the ocean water as pure water for this estimate)
4.186*E15 J
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9. If 2.8E5 J of energy is supplied to a flask of liquid oxygen at ­183 oC, how much oxygen can evaporate?
1.33 kg
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10. What Mass of Steam at 100 oC must be added to 1.00 kg of ice at 0 oC to yield water at 20 oC?
.163 kg
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April 16, 2013
State your mass and estimate your volume (you are mostly water)
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April 16, 2013
A geologist finds that a Moon rock whose mass is 9.28 kg has an apparent mass of 6.18 kg when submerged in water. What is the density of the rock?
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A crane lifts the 18,000 kg steel hull of a ship out the water. Determine the tension in the crane's cable when the hull is submerged in the water
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