If you have a heat engine with a hot reservoir of 515 k and a cold reservoir of 190 k, what is the maximum possible thermal efficiency of the system?

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The equation for the thermal efficiency of a system is given by n = Tc/Thx100 where n is the thermal efficiency, Tc is the temperature of the cold reservoir and Th is the temperature of the hot reservoir. Dividing 190 by 515 gives us an efficiency of 36.9%.

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Is a  vector quantity  that refers to "the rate at which an object changes its position." imagine a person moving rapidly - one step forward and one step back - always returning to the original starting position. while this might result in a frenzy of activity, it would result in a zero velocity. because the person always returns to the original position, the motion would never result in a change in position. since velocity is defined as the rate at which the position changes, this motion results in zero velocity. if a person in motion wishes to maximize their velocity, then that person must make every effort to maximize the amount that they are displaced from their original position. every step must go into moving that person further from where he or she started. for certain, the person should never change directions and begin to return to the starting position.