A heat conducting rod,  0.90 m long, is made of an aluminum section that is  0.10 m long, and a copper section that is  long. Both sections have cross-sectional areas of  The aluminum end is maintained at a temperature of  and the copper end is at . The thermal conductivity of aluminum is 205 W/m ∙ K and of copper is 385 W/m ∙ K. Steady state has been reached, and no heat is lost through the well-insulated sides of the rod. The temperature of the aluminum-copper junction in the rod is closest to

The figure (not to scale) shows a pV diagram for 1.8 g of helium gas (He) that undergoes the process 1 → 2 → 3. Find the value of V1. The ideal gas constant is R = 8.314 J/mol ∙ K = 0.0821 L ∙ atm/mol ∙ K, and the atomic weight of helium is 4.0 g/mol. 

If the pressure of an ideal monatomic gas is increased while the number of moles is kept constant, what always happens to the average translational kinetic energy of one atom of the gas? Choose the best answer.  

Two metal rods, one silver and the other copper, are both attached to a steam chamber as shown in the figure, with a temperature of 100°C, at one end, and an ice water bath, with a temperature of 0°C, at the other. The rods are 5.0 cm long and have a square cross-section, 2.0 cm on a side. When steady state has been reached, how much heat flows through the two rods in 1.0 min? The thermal conductivity of silver is 417 W/(m ∙ K), and that of copper is 395 W/(m ∙ K). No heat is exchanged between the rods and the surroundings, except at their ends.

A 2-mol sample of oxygen gas expands slowly and adiabatically from a pressure of 5 atm and a volume of 12.0L to a final volume of 30.0L. Find the change of internal energy. 

Two liquids are mixed in an insulated container. The final temperature is below both initial temperatures. Best explanation:

A Carnot heat engine absorbs heat Q from a hot reservoir at 127oC and exhausts heat to a cold reservoir at 27oC. How much heat is exhausted to the cold reservoir?

What are three key reasons for international trade?

What is an advantage of a sole proprietorship versus a large corporation?

In a free-market economy what primarily determines the allocation of resources?