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GR0877 Problem 35

PROBLEM STATEMENT: This problem is still being typed.

SOLUTION: (B) Assuming a heat pump is an ideal Carnot engine for its efficiency one has \eta = W/Q_H = 1 - T_C/T_H, where W is the work done by the system, Q_H is the heat put into the system, T_C, T_H are the absolute temperatures of the cold and hot reservoirs. W = Q_H(1 - T_C/  T_H) = 15000 \cdot (1 - 280/300) = 15000/15 = 1000 (J).

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Categories: 0877 Tags: , , , ,
  1. notstudying
    27.08.2015 at 08:11

    Why is the efficiency equal to 1 – T_c/T_H rather than T_H(1-T_C/T_H)? http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/carnot.html#c2

  2. 24.09.2015 at 22:52

    From hyper physics I got CP= Qh/W (http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/heatpump.html), but here you used n= W/Qh. Are they not the same thing? Thanks!

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