A 70.0-kg block of ice at 0.00°C breaks off from a glacier, slides along the frictionless ice to the ground from a height of 2.43 m, and then slides along a horizontal surface consisting of gravel and dirt. Find how much of the mass of the ice is melted by the friction with the rough surface, assuming 75.0% of the internal energy generated stays in the ice. Latent heat of fusion (Lf) for water 333,700 J/kg.

The rate at which a resting person converts food energy is called one’s basal metabolic rate (BMR). Assume that the resulting internal energy leaves a person’s body by radiation and convection of dry air. When you jog, most of the food energy you burn above your BMR becomes internalenergy that would raise your body temperature if it were not eliminated. Assume that evaporation of perspiration is the mechanism for eliminating this energy. Suppose a person is jogging for “maximum fat burning,” converting food energy at the rate 400 kcal/h above his BMR, and putting out energy by work at the rate 60.0 W. Assume that the heat of evaporation of water at body temperature is equal to its heat of vaporization at 100°C. (a) Determine the hourly rate at which water must evaporate from his skin. (b) When you metabolize fat, the hydrogen atoms in the fat molecule are transferred to oxygen to form water. Assume that metabolism of 1.00 g of fat generates 9.00 kcal of energy and produces 1.00 g of…

A 283 g silver figure of a polar bear is dropped into the 249 g aluminum cup of a well-insulated calorimeter containing 265 g of liquid water at 20.9°C. The bear's initial temperature is 98.5°C. What is the final temperature of the water, cup, and bear when they reach thermal equilibrium? The specific heats of silver, aluminum, and liquid water are, respectively, 234 J/ (kg-K), 910 J/ (kg-K), and 4190 J/ (kg-K). final temperature: °C

A 95.0-kg block of ice at 0.00°C breaks off from a glacier, slides along the frictionless ice to the ground from a height of 2.43 m, and then slides along a horizontal surface consisting of gravel and dirt. Find how much of the mass of the ice is melted by the friction with the rough surface, assuming 75.0% of the internal energy generated stays in the ice. Latent heat of fusion (Lf) for water 333,700 J/kg.

Problem 11:   A mass m = 125 kg of lava at TH = 1155° C emerges from a volcano deep in the ocean. At this depth, the ocean water is at a temperature of TC = 2.1° C, and the lava cools and solidifies.The specific heat capacity of the lava for this process is c = 840 J/kg⋅°C and the latent heat of fusion of the lava is Lf = 4.0 × 105 J/kg.Assume that the temperature of the ocean does not change in this process. Part (a)  The lava cools to 700.0° C before solidifying. What is the change in entropy ΔS1 of the lava in joules per kelvin during this process? Part (b)  Calculate the change in entropy of the ocean waters ΔS2 in joules per kelvin during the cooling of the molten lava. Part (c)  Calculate the change in entropy of the lava ΔS3 in joules per kelvin when it solidifies. Part (d)  Calculate the entropy change of the ocean ΔS4 in joules per kelvin due to the solidification of the lava.

Oxy-fuel combustion power plants use pulverized coal particles as fuel to burn in a pure oxygen environment to generate electricity. Before entering the furnace, pulverized spherical coal particles with an average diameter of 300 mm, are being transported at 2 m/s through a 3-m long heated tube while suspended in hot air. The air temperature in the tube is 900°C and the average convection heat transfer coefficient is 250 W/m2·K. Determine the temperature of the coal particles at the exit of the heated tube, if the initial temperature of the particles is 20°C.

Assume Lake Michigan contains 4.90 x 1012 m³ of water, and assume the water's density is that of water at 20°C and 1 atm. (a) How much energy (in J) is required to raise the temperature of that volume of water from 12.2°C to 24.4°C? 4.1E19 From the density of water and the volume, what is the mass of the water? What is specific heat? How is it related to the energy input, mass, and temperature change? Use it to solve for the energy. Be careful with units. J (b) How many years would it take to supply this amount of energy by using a power of 1,400 MW generated by an electric power plant? 926 How is power related to energy and time? Knowing the energy from part (a), can you find the time? Be careful with units. Make sure you convert the time in seconds to years. yr

A 155 g copper bowl contains 230 g of water, both at 20.0°C. A very hot 300 g copper cylinder is dropped into the water, causing the water to boil, with 4.05 g being converted to steam. The final temperature of the system is 100°C. Neglect energy transfers with the environment. (a) How much energy (in calories) is transferred to the water as heat? 8.6 X kcal (b) How much energy (in calories) is transferred to the bowl? 55 X kcal (c) What is the original temperature of the cylinder? 553.6 X °C Did you use the idea of conservation of energy? That is, did you equate the sum of the energy transfers to zero? For the bowl and cylinder, did you substitute the expression relating an energy transfer, the specific heat, the mass, and the temperature change? For the water, did you use the same expression to get the water to the boiling point? Did you also include an expression for the heat of vaporization? Did you use the given final temperature for each of the three materials?

An insulated Thermos contains 140 cm³ of hot coffee at 92.0°C. You put in a 18.0 g ice cube at its melting point to cool the coffee. By how many degrees has your coffee cooled once the ice has melted and equilibrium is reached? Treat the coffee as though it were pure water and neglect energy exchanges with the environment. The specific heat of water is 4186 J/kg-K. The latent heat of fusion is 333 kJ/kg. The density of water is 1.00 g/cm³. Number i Units

A well-insulated aluminum calorimeter cup with mass of 231 g contains 271 g of liquid water at 25.1 °C. A 295-g silver figure of polar bear, with initial temperature of 96.5 °C, is dropped into the water. What is the final temperature of the water, cup, and bear when they reach thermal equilibrium? The specific heats of silver, aluminum, and liquid water are, respectively, 234 J/(kg · K), 910 J/(kg · K), and 4190 J/(kg · K). final temperature: