How much heat energy must be added to a 6.0-cm-diameter copper sphere to raise its temperature from −50°C to 150°C?

500 J of heat energy are transferred to a gas during a process in which the gas expands at constant pressure from 400 cm³ to 800 cm³. The gas's thermal energy increases by 300 J during this process. What is the gas pressure?

What is the maximum mass of ethyl alcohol you could boil with 1000 J of heat, starting from 20°C?

Two cars collide head-on while each is traveling at 80 km/h. Suppose all their kinetic energy is transformed into the thermal energy of the wrecks. What is the temperature increase of each car? You can assume that each car's specific heat is that of iron.

A rapidly spinning paddle wheel raises the temperature of 200 mL of water from 21°C to 25°C. How much heat is transferred?

One way you keep from overheating is by perspiring. Evaporation—a phase change—requires heat, and the heat energy is removed from your body. Evaporation is much like boiling, only water's heat of vaporization at 35°C is a somewhat larger 24×10⁵ J/kg because at lower temperatures more energy is required to break the molecular bonds. Very strenuous activity can cause an adult human to produce 30 g of perspiration per minute. If all the perspiration evaporates, rather than dripping off, at what rate (in J/s) is it possible to exhaust heat by perspiring?

Draw a first-law bar chart (see Figure 19.12) for the gas process in FIGURE EX19.7.