In a game of football outdoors on a cold day, a player will begin to feel exhausted after using approximately 8.0 × 105 J of internal energy. (a) One player, dressed too lightly for the weather, has to leave the game after losing 6.6 × 105 J of heat. How much work has he done? (b) Another player, wearing clothes that offer better protection against heat loss, is able to remain in the game long enough to do 2.9 × 105 J of work. What is the magnitude of the heat that he has lost? (a) number units (b) number units

A system undergoes a two-step process. In the first step, the internal energy of the system increases by 230 J when 166 J of work is done on the system. In the second step, the internal energy of the system increases by 115 J when 191 J of work is done on the system. For the overall process, find the heat added to the system (including sign).

A Carnot heat engine uses a hot reservoir consisting of a large amount of boiling water and a cold reservoir consisting of a large tub of ice and water. In 5 minutes of operation of the engine, the heat rejected by the engine melts a mass of ice equal to 3.25×10−2 kg. Throughout this problem use Lf=3.34×105J/kg for the heat of fusion for water. During this time, how much work W is performed by the engine?

A storage building with well-insulated walls and containing 750 m³ of air at 275 K is heated at constant pressure (atmospheric). Consider air to be an ideal diatomic gas. (a) Determine the energy (in kJ) required to increase the temperature of the air in the building by 2.30°C. kJ (b) Determine the mass (in kg) this amount of energy could lift through a height 2.30 m. kg

Consider the change in the internal energy of a system. -What is the change in the internal energy, in joules, of a system that does 4.725 × 105 J of work, while 3.2 × 106 J of heat is transferred into the system and 7.8 × 106 J of heat is transferred from the system to the environment?

Suppose that you have left a 200 mL cup of coffee sitting until it has cooled to 30◦ C, which you find totally unacceptable. Your microwave oven draws 1100W of electrical power when it is running. If it takes 45s for this microwave oven to raise the temperature of the coffee to 60◦ C, what is the efficiency of heating with this oven? You will need to use the fact that 4.2 J of energy is required to raise the temperature of 1.0 mL of coffee by 1.0◦ C.

Question 4. A 5.0 kg block of aluminium is heated from 20°C to 90°C at atmospheric pressure. Find (a) the work done by the aluminium, (b) the amount of energy transferred to it by heat, and (c) the increase in internal energy.

An uninsulated container holds 3.5 mol of an ideal gas at an initial temperature of 300 K. The gas is compressed by a movable piston, and 500 J of work is done on the gas while being compressed. If the final temperature of the gas is 400 K, how much heat flows in or out of the gas during this process?

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?

A pot containing 1.70 kg of water is sitting on a hot stove, and the water is stirred violently by a mixer that does 6.40 kJ of mechanical work on the water. The temperature of the water rises by 4.00°C. What quantity of heat flowed into the water from the stove during the process? The specific heat of water is 4.186 kJ/kg·K.