Engine 1 has an efficiency of 0.13 and requires 7200 j of input heat to perform a certain amount of work. engine 2 has an efficiency of 0.28 and performs the same amount of work. how much input heat does the second engine require?

3,342.86J

Explanation:

Engine 1

Quantity of Input Heat,  = 7200J

Efficiency,  η = 0.13

                           Efficiency,  η

                           ⇒ W = η

                                W = 0.13 × 7200

                                W = 936J  

Engine 2

Efficiency,  η = 0.28

Since Engine 2 performs same amount of work as Engine 1, then,

                 Work-done by Engine 2 = Work-done by Engine 1

                                       W₂ = W₁ = 936J

                 Efficiency,  η

                  = W / η

                  = 3,342.86J

The input heat require by  the second engine is 3,342.86J

the working equation for the angular size is the product of the physical size and 360 degrees divided by the product of two pi and distance from earth. the minimum size would be 0.559 degrees while the maximum size would be 0.49 degrees.