A Heat Engine has a power output of 17.4 kW and rejects heat to a  heat sink at a rate of 2.69 MJ/minute. The Thermal Efficiency of this Engine is:Group of answer choices72%15%28.6%38.8%

To find the thermal efficiency of the engine, we first need to understand the concept of thermal efficiency. It is the ratio of work done to the heat absorbed.

The formula for thermal efficiency (η) is:

η = Work Output / Heat Input

Given: Power output (Work Output) = 17.4 kW = 17400 W (since 1 kW = 1000 W) Heat rejected = 2.69 MJ/minute = 2.69 * 10^6 J/minute = 2.69 * 10^6 J/60 s = 44833.33 J/s

But this is the heat rejected, not the heat input. The heat input is the sum of the work output and the heat rejected. So,

Heat Input = Work Output + Heat Rejected Heat Input = 17400 W + 44833.33 W = 62233.33 W

Now, we can substitute these values into the formula for thermal efficiency:

η = Work Output / Heat Input η = 17400 W / 62233.33 W = 0.2796

To convert this to a percentage, we multiply by 100:

η = 0.2796 * 100 = 27.96%

So, the thermal efficiency of the engine is approximately 28%, which is closest to 28.6% from the given options. Therefore, the correct answer is 28.6%.