Chapter 1, Problem 81A

To determine

ToFind:The reasonable value of the diameter of the engine.

Explanation of Solution

Introduction:

A jet engine is designed for very precise dimensions and the dimensions become very important for the perfect functioning of the jet plane. The dimensions of the engine of a jet plane are usually 3 m to 3.5 m in diameter. The jet planes with such diameters create enough thrust for the propulsion of jet plane of standard size.

If the diameter of the jet engine is varied out of proportions, it directly affects the proper functioning of the jet plane. The diameter as high as 80 m is very much out of proportion and it is certainly unreasonable.

The jet plane needs to remain in air for long hours, therefore, the jet planes cannot be of any random size. It cannot happen that to produce excess thrust, just the diameters of the jet engine are increased. If the diameter of the jet engine is varied, other dimensions of the jet plane need to be changed in the same proportions.

Conclusion:

Therefore, the diameter value of 3 to 3.5 m is reasonable for the jet engine and the excessively disproportionate diameter of 80 m is highly unreasonable.