This scale drawing of a wind turbine has been done for a mag

This scale drawing of a wind turbine has been done for a magazine article. The actual turbine has a hub height of 80 m. What is the diameter of the actual rotor? Show your work. What scale factor was used to create, the diagram? Show your work.

Solution

This is a scaled drawing. That means you will have to actually put a scale next to your drawing and get the scaled length and then mutiply that length with the scale factor to get the actual height.

I will solve the problem in terms of variables which you can subtitute and determine the values once you are done measuring with scale.

Let us assume that the height of the topmost point in the diagram as x cm. You need to notice that the height of the topmost point from the ground would be equal to the sum of the hub height and length of the rotor blade.

Also, rotor blade is half the radius of the rotor diameter.

Plus, we will also assume that the bar height when measure with a scale on paper is y cm.

Now, we know that the actual bar height is 80 m,

Part b.) Hence the scale factor is (8000/y) [Change 80m to cms]

Now the rotor diameter as per our measurements would be 2(x-y)

Part a.) That is the actual rotor diameter = 2(x-y) * (8000/y)

NOTE: You just need to measure the height of the topmost point in cms and put it as x and then the hub height and put it as y.

Also, the scale factor as I have taken is the ratio of actual height to the drawn height. It needs to be understood that at places you may find the other way around. You just need to understand whether you are scalin up or scaling down and take the ratio appropriately.