1.(a)A Carnot engine operates between a hot reservoir at 320K and a cold one at 260K. If the engine absorbs 500J as heat cycle at the hot reservoir, how much work per cycle does it deliver? (b)If the engine working in reverse functions as a refrigerator between the same two reservoirs,how much work per cycle must be supplied to remove 1000J as heat from the cold reservoir? 2.An electric dipole with dipole moment →p=(3.00i+4.00j)(1.24x10^-30 C‧m) is in an electric field →E=(4000 N/C)i (a)What is the potential energy of the electric dipole? (b)What is the torque acting on it ? (c)If an external agent turns the dipole until its electric dipole moment is →p=(-4.00i+3.00j)(1.24x10^-30 C‧m), how much work is done by the agen? 3.在温度T很低的时候,许多固体的定容摩耳比热Cv与温度的关系可以近似为Cv=AT^3, 其中A与特定的材料有关,对铝而言,A=3.15x10^-5 J/molx k^4. 求；4.00 mol 的铝,温度由5.00K上升到10.0K时,entropy(熵)的改变量. 请版友帮解感谢 感谢帮忙 --

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