34 O Samples A and B are at different initial temperatures when they are placed in a thermally insulated container and al- lowed to come to thermal equilibrium. Figure 18-34a gives their temperatures T versus time t. Sample A has a mass of 5.0 kg; sam- ple B has a mass of 1.5 kg. Figure 18-34b is a general plot for the material of sample B. It shows the temperature change AT that the material undergoes when energy is transferred to it as heat Q. The change AT is plotted versus the energy Q per unit mass of the material, and the scale of the vertical axis is set by AT, = 4.0 C. What is the specific heat of sample A? 100 AT, 60 в 20 10 20 8. 16 t (min) Q/m (kJ/kg) (a) (6) ()) LV (0.)L

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Ice at -12.1 °C and steam at 121 °C are brought together at atmospheric pressure in a perfectly insulated container. After thermal equilibrium is reached, the liquid phase at 44.1 °C is present. Ignoring the container and the equilibrium vapor pressure of the liquid at 44.1 °C, find the ratio of the mass of steam to the mass of ice. The specific heat capacity of steam is 2020 J/(kg C°). af Number i Initial state Units Steam - Ice Equilibrium Water

A 1.17 kg hammer strikes a 20 g brass nail into a wood board. The nail is horizontally aligned and at the moment of impact with the nail, the hammer had a speed of 9.1 m/s. Assume both the hammer and the nail come to a stop and that all of the thermal energy generated goes into heating the nail. Determine how much the temperature of the nail will increase after one hit and how many hits it will take to increase its temperature 88°C ΔT after one hit = Minimum number of hits needed to increase the temperature by at least 88°C =

a cup of coffee sits on a table in an insulated mug. to coool the coffee down a ice block is added. the inital mass of coffee in the mug is 90g. the intial temperature of the coffee is 90 degree celsius. the ice block has started to melt and is then put into the coffee. the ice melts and the new temperature of the cofee is 78 degree c and the new mass is 110g. the ice block (final-intital mass) is 20g. what are teh tempeartuare changes for the coffee and ice (started at 0 degree celsius) also if specific heat of water is used for both the coffee and ice waht is the heat energy lost by the coffee and the heat energy gained by the ice after it melted?